Hide comments and threads from specific user

/**
* Implements hook_preprocess_HOOK().
*/
function blacklist_preprocess_field(&$variables) {
 $field_name = $variables['element']['#field_name'];
 if ($field_name === 'comment_forum') {
   /** @var \Drupal\node\NodeInterface $node */
   $node = $variables['element']['#object'];
   $comment_storage = \Drupal::entityTypeManager()->getStorage('comment');
   // Select comments from blacklisted user.
   $query = $comment_storage->getQuery()
     ->accessCheck()
     ->condition('entity_id', $node->id())
     ->condition('entity_type', 'node')
     ->condition('uid', '963083') // DEBUG!!!!
     ->condition('status', 1)
     ->sort('created', 'DESC');
   $comment_ids = $query->execute();
   $comments = $comment_storage->loadMultiple($comment_ids);
   /** @var \Drupal\comment\CommentInterface $comment */
   foreach ($comments as $comment) {
     // Get all comments from threads from blacklisted user.
     $thread_prefix = explode('.', $comment->getThread())[0];
     $query = \Drupal::entityQuery('comment')
       ->accessCheck()
       ->condition('entity_id', $comment->getCommentedEntityId())
       ->condition('thread', $thread_prefix, 'STARTS_WITH')
       ->sort('thread');
     $cids = $query->execute();
     // Hide comments and threads from blacklisted user.
     foreach ($cids as $cid) {
       unset($variables['comments'][$cid]);
     }
   }
 }
}