diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index fa1e3f209c322..b9b109b5d08fe 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -76,7 +76,6 @@ includes:
 	- tests/phpstan/baselines/property.defaultValue.neon
 	- tests/phpstan/baselines/property.nonObject.neon
 	- tests/phpstan/baselines/property.notFound.neon
-	- tests/phpstan/baselines/property.onlyWritten.neon
 	- tests/phpstan/baselines/property.phpDocType.neon
 	- tests/phpstan/baselines/property.private.neon
 	- tests/phpstan/baselines/property.protected.neon
diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-template-autosaves-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-template-autosaves-controller.php
index dbdca575089fc..4dd5cb21c0cc5 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-template-autosaves-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-template-autosaves-controller.php
@@ -15,14 +15,6 @@
  * @see WP_REST_Autosaves_Controller
  */
 class WP_REST_Template_Autosaves_Controller extends WP_REST_Autosaves_Controller {
-	/**
-	 * Parent post type.
-	 *
-	 * @since 6.4.0
-	 * @var string
-	 */
-	private $parent_post_type;
-
 	/**
 	 * Parent post controller.
 	 *
@@ -56,9 +48,8 @@ class WP_REST_Template_Autosaves_Controller extends WP_REST_Autosaves_Controller
 	 */
 	public function __construct( $parent_post_type ) {
 		parent::__construct( $parent_post_type );
-		$this->parent_post_type = $parent_post_type;
-		$post_type_object       = get_post_type_object( $parent_post_type );
-		$parent_controller      = $post_type_object->get_rest_controller();
+		$post_type_object  = get_post_type_object( $parent_post_type );
+		$parent_controller = $post_type_object->get_rest_controller();
 
 		if ( ! $parent_controller ) {
 			$parent_controller = new WP_REST_Templates_Controller( $parent_post_type );
diff --git a/tests/phpstan/baselines/property.onlyWritten.neon b/tests/phpstan/baselines/property.onlyWritten.neon
deleted file mode 100644
index f4b740e1bdf02..0000000000000
--- a/tests/phpstan/baselines/property.onlyWritten.neon
+++ /dev/null
@@ -1,25 +0,0 @@
-# PHPStan baseline for the `property.onlyWritten` errors in WordPress core.
-#
-# https://phpstan.org/error-identifiers/property.onlyWritten
-#
-# Each entry is scoped to a single file and carries an exact occurrence count,
-# so that a new instance is reported as a new error rather than being absorbed
-# silently. Fixing an occurrence therefore means decrementing or removing its
-# entry here as part of the same change.
-#
-# The goal is to empty this file and delete it, along with the `includes` entry
-# for it in phpstan.neon.dist.
-#
-# Generated by `composer phpstan:baselines`. Do not edit by hand; regenerate with
-#
-#     composer phpstan:baselines -- --identifier=property.onlyWritten
-#
-# which reruns the analysis with this file suppressed so the errors surface again.
-
-parameters:
-	ignoreErrors:
-		-
-			message: '#^Property WP_REST_Template_Autosaves_Controller\:\:\$parent_post_type is never read, only written\.$#'
-			identifier: property.onlyWritten
-			count: 1
-			path: ../../../src/wp-includes/rest-api/endpoints/class-wp-rest-template-autosaves-controller.php