diff --git a/core/modules/simpletest/simpletest.install b/core/modules/simpletest/simpletest.install
index 2bbc528d19..dff690bf27 100644
--- a/core/modules/simpletest/simpletest.install
+++ b/core/modules/simpletest/simpletest.install
@@ -24,8 +24,8 @@ function simpletest_requirements($phase) {
 
   $requirements['deprecation'] = [
     'title' => t('Simpletest'),
-    'value' => t('The Drupal core Simpletest module is deprecated for removal in Drupal 9. It should not be enabled on production sites. You will need to uninstall the module before updating. See https://www.drupal.org/node/3091784 for alternatives.'),
-    'severity' => REQUIREMENT_WARNING,
+    'value' => t('The Drupal core Simpletest module is deprecated for removal in Drupal 9. It should not be enabled on production sites. See https://www.drupal.org/node/3091784 for alternatives.'),
+    'severity' => $phase === 'runtime' ? REQUIREMENT_WARNING : REQUIREMENT_NOTICE,
   ];
 
   $has_phpunit = class_exists(TestCase::class);
diff --git a/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php b/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
index 87822cf9dd..d7bad28513 100644
--- a/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
+++ b/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
@@ -298,12 +298,6 @@ protected function runUpdates() {
       $this->fail('Missing zlib requirement for update tests.');
       return FALSE;
     }
-    // We need to make sure that the Simpletest module is not installed or the
-    // update will not be allowed to continue.
-    if (\Drupal::moduleHandler()->moduleExists('simpletest')) {
-      \Drupal::getContainer()->get('module_installer')->uninstall(['simpletest']);
-      $this->rebuildContainer();
-    }
     // The site might be broken at the time so logging in using the UI might
     // not work, so we use the API itself.
     drupal_rewrite_settings([