Drupal 8 and 9 delete file programmatically

Code that can be used to permanently delete unused/orphaned files in drupal 9 and 8.
// get all files ids
  $fids = \Drupal::entityQuery('file')->execute();
  $file_usage = \Drupal::service('file.usage');
  // loop all fids and load files by fid
  foreach ($fids as $fid) {
    $file = \Drupal\file\Entity\File::load($fid);
    $usage = $file_usage->listUsage($file);
    // check if file not used
    if (count($usage) == 0) {
      $file->delete();
    }
  }