diff --git a/core/core.services.yml b/core/core.services.yml
index de408ad9f30e4659d03201cafabc2a5fa8988ed5..680c23b80840d1bf8647d6acd3e4446b47c56076 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -575,7 +575,7 @@ services:
       - { name: event_subscriber }
   entity.definition_update_manager:
     class: Drupal\Core\Entity\EntityDefinitionUpdateManager
-    arguments: ['@entity.manager', '@entity.last_installed_schema.repository']
+    arguments: ['@entity.manager']
   entity.last_installed_schema.repository:
     class: Drupal\Core\Entity\EntityLastInstalledSchemaRepository
     arguments: ['@keyvalue']
diff --git a/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManager.php b/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManager.php
index c5d0abd5028ae456ad6b1c417781afe66e604493..d9a4d843f517e8accc3aa89fbefdfaacf57e5e76 100644
--- a/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManager.php
@@ -21,29 +21,14 @@ class EntityDefinitionUpdateManager implements EntityDefinitionUpdateManagerInte
    */
   protected $entityManager;
 
-  /**
-   * The last installed schema repository.
-   *
-   * @var \Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface
-   */
-  protected $entityLastInstalledSchemaRepository;
-
   /**
    * Constructs a new EntityDefinitionUpdateManager.
    *
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager.
-   * @param \Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface $entity_last_installed_schema_repository
-   *   The last installed schema repository service.
    */
-  public function __construct(EntityManagerInterface $entity_manager, EntityLastInstalledSchemaRepositoryInterface $entity_last_installed_schema_repository = NULL) {
+  public function __construct(EntityManagerInterface $entity_manager) {
     $this->entityManager = $entity_manager;
-
-    if (!isset($entity_last_installed_schema_repository)) {
-      @trigger_error('The $entity_last_installed_schema_repository parameter was added in Drupal 8.6.x and will be required in 9.0.0. See https://www.drupal.org/node/2973262.', E_USER_DEPRECATED);
-      $entity_last_installed_schema_repository = \Drupal::service('entity.last_installed_schema.repository');
-    }
-    $this->entityLastInstalledSchemaRepository = $entity_last_installed_schema_repository;
   }
 
   /**
@@ -78,7 +63,7 @@ public function getChangeSummary() {
       // Process field storage definition changes.
       if (!empty($change_list['field_storage_definitions'])) {
         $storage_definitions = $this->entityManager->getFieldStorageDefinitions($entity_type_id);
-        $original_storage_definitions = $this->entityLastInstalledSchemaRepository->getLastInstalledFieldStorageDefinitions($entity_type_id);
+        $original_storage_definitions = $this->entityManager->getLastInstalledFieldStorageDefinitions($entity_type_id);
 
         foreach ($change_list['field_storage_definitions'] as $field_name => $change) {
           switch ($change) {
@@ -123,7 +108,7 @@ public function applyUpdates() {
       // Process field storage definition changes.
       if (!empty($change_list['field_storage_definitions'])) {
         $storage_definitions = $this->entityManager->getFieldStorageDefinitions($entity_type_id);
-        $original_storage_definitions = $this->entityLastInstalledSchemaRepository->getLastInstalledFieldStorageDefinitions($entity_type_id);
+        $original_storage_definitions = $this->entityManager->getLastInstalledFieldStorageDefinitions($entity_type_id);
 
         foreach ($change_list['field_storage_definitions'] as $field_name => $change) {
           $storage_definition = isset($storage_definitions[$field_name]) ? $storage_definitions[$field_name] : NULL;
@@ -138,17 +123,10 @@ public function applyUpdates() {
    * {@inheritdoc}
    */
   public function getEntityType($entity_type_id) {
-    $entity_type = $this->entityLastInstalledSchemaRepository->getLastInstalledDefinition($entity_type_id);
+    $entity_type = $this->entityManager->getLastInstalledDefinition($entity_type_id);
     return $entity_type ? clone $entity_type : NULL;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function getEntityTypes() {
-    return $this->entityLastInstalledSchemaRepository->getLastInstalledDefinitions();
-  }
-
   /**
    * {@inheritdoc}
    */
@@ -195,7 +173,7 @@ public function installFieldStorageDefinition($name, $entity_type_id, $provider,
    * {@inheritdoc}
    */
   public function getFieldStorageDefinition($name, $entity_type_id) {
-    $storage_definitions = $this->entityLastInstalledSchemaRepository->getLastInstalledFieldStorageDefinitions($entity_type_id);
+    $storage_definitions = $this->entityManager->getLastInstalledFieldStorageDefinitions($entity_type_id);
     return isset($storage_definitions[$name]) ? clone $storage_definitions[$name] : NULL;
   }
 
@@ -233,7 +211,7 @@ protected function doEntityUpdate($op, $entity_type_id) {
         break;
 
       case static::DEFINITION_UPDATED:
-        $original = $this->entityLastInstalledSchemaRepository->getLastInstalledDefinition($entity_type_id);
+        $original = $this->entityManager->getLastInstalledDefinition($entity_type_id);
         $this->entityManager->onEntityTypeUpdate($entity_type, $original);
         break;
     }
@@ -284,7 +262,7 @@ protected function getChangeList() {
     $change_list = [];
 
     foreach ($this->entityManager->getDefinitions() as $entity_type_id => $entity_type) {
-      $original = $this->entityLastInstalledSchemaRepository->getLastInstalledDefinition($entity_type_id);
+      $original = $this->entityManager->getLastInstalledDefinition($entity_type_id);
 
       // @todo Support non-storage-schema-changing definition updates too:
       //   https://www.drupal.org/node/2336895.
@@ -299,7 +277,7 @@ protected function getChangeList() {
         if ($this->entityManager->getStorage($entity_type_id) instanceof DynamicallyFieldableEntityStorageInterface) {
           $field_changes = [];
           $storage_definitions = $this->entityManager->getFieldStorageDefinitions($entity_type_id);
-          $original_storage_definitions = $this->entityLastInstalledSchemaRepository->getLastInstalledFieldStorageDefinitions($entity_type_id);
+          $original_storage_definitions = $this->entityManager->getLastInstalledFieldStorageDefinitions($entity_type_id);
 
           // Detect created field storage definitions.
           foreach (array_diff_key($storage_definitions, $original_storage_definitions) as $field_name => $storage_definition) {
diff --git a/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManagerInterface.php b/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManagerInterface.php
index a219f3c046ceba8a229555990f390f657f1fa1ad..7754170dbb4410f39455ec2bd086735b35bf1b02 100644
--- a/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManagerInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityDefinitionUpdateManagerInterface.php
@@ -108,18 +108,6 @@ public function applyUpdates();
    */
   public function getEntityType($entity_type_id);
 
-  /**
-   * Returns all the entity type definitions, ready to be manipulated.
-   *
-   * When needing to apply updates to existing entity type definitions, this
-   * method should always be used to retrieve all the definitions ready to be
-   * manipulated.
-   *
-   * @return \Drupal\Core\Entity\EntityTypeInterface[]
-   *   The last installed entity type definitions, keyed by the entity type ID.
-   */
-  public function getEntityTypes();
-
   /**
    * Installs a new entity type definition.
    *
diff --git a/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepository.php b/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepository.php
index 1230ecc15e7de3b69ad612a58c162d9e5ed1768f..61300125c9948380f37491974bf0cc91005f8629 100644
--- a/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepository.php
+++ b/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepository.php
@@ -34,27 +34,6 @@ public function getLastInstalledDefinition($entity_type_id) {
     return $this->keyValueFactory->get('entity.definitions.installed')->get($entity_type_id . '.entity_type');
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function getLastInstalledDefinitions() {
-    $all_definitions = $this->keyValueFactory->get('entity.definitions.installed')->getAll();
-
-    // Filter out field storage definitions.
-    $entity_type_definitions = array_filter($all_definitions, function ($key) {
-      return substr($key, -12) === '.entity_type';
-    }, ARRAY_FILTER_USE_KEY);
-
-    // Ensure that the returned array is keyed by the entity type ID.
-    $keys = array_keys($entity_type_definitions);
-    $keys = array_map(function ($key) {
-      $parts = explode('.', $key);
-      return $parts[0];
-    }, $keys);
-
-    return array_combine($keys, $entity_type_definitions);
-  }
-
   /**
    * {@inheritdoc}
    */
diff --git a/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepositoryInterface.php b/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepositoryInterface.php
index af910bb69004350caaffb54dc432f4d6d1bc8520..53f02a00063f30d7f969559f5137cfc712288ff7 100644
--- a/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepositoryInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepositoryInterface.php
@@ -41,34 +41,6 @@ interface EntityLastInstalledSchemaRepositoryInterface {
    */
   public function getLastInstalledDefinition($entity_type_id);
 
-  /**
-   * Gets the entity type definitions in their most recently installed state.
-   *
-   * During the application lifetime, entity type definitions can change. For
-   * example, updated code can be deployed. The
-   * \Drupal\Core\Entity\EntityTypeManagerInterface::getDefinitions() method
-   * will always return the definitions as determined by the current codebase.
-   * This method returns the definitions from the last time that a
-   * \Drupal\Core\Entity\EntityTypeListener event was completed. In other words,
-   * the definitions that the entity type's handlers have incorporated into the
-   * application state. For example, if the entity type's storage handler is
-   * SQL-based, the definition for which database tables were created.
-   *
-   * Application management code can check if
-   * \Drupal\Core\Entity\EntityTypeManagerInterface::getDefinitions() differs
-   * from getLastInstalledDefinitions() and decide whether to:
-   * - Invoke the appropriate \Drupal\Core\Entity\EntityTypeListenerInterface
-   *   event so that handlers react to the new definitions.
-   * - Raise a warning that the application state is incompatible with the
-   *   codebase.
-   * - Perform some other action.
-   *
-   * @return \Drupal\Core\Entity\EntityTypeInterface[]
-   *   An array containing the installed definition for all entity types, keyed
-   *   by the entity type ID.
-   */
-  public function getLastInstalledDefinitions();
-
   /**
    * Stores the entity type definition in the application state.
    *
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
index 1a743eceebed491d2e95ad1e5c5d71f9389fc550..01044f724a1d314060ed3f2efa3b86244676b396 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
@@ -20,8 +20,6 @@
 /**
  * Tests EntityDefinitionUpdateManager functionality.
  *
- * @coversDefaultClass \Drupal\Core\Entity\EntityDefinitionUpdateManager
- *
  * @group Entity
  */
 class EntityDefinitionUpdateTest extends EntityKernelTestBase {
@@ -1182,18 +1180,4 @@ public function testInitialValueFromFieldErrorHandling() {
     }
   }
 
-  /**
-   * @covers ::getEntityTypes
-   */
-  public function testGetEntityTypes() {
-    $entity_type_definitions = $this->entityDefinitionUpdateManager->getEntityTypes();
-
-    // Ensure that we have at least one entity type to check below.
-    $this->assertGreaterThanOrEqual(1, count($entity_type_definitions));
-
-    foreach ($entity_type_definitions as $entity_type_id => $entity_type) {
-      $this->assertEquals($this->entityDefinitionUpdateManager->getEntityType($entity_type_id), $entity_type);
-    }
-  }
-
 }