Chosen strings are not translatable

Chosen strings are not translatable. Are we should to add them as translatable markup?

$options = array(
    'disable_search' => (bool) $chosen_conf->get('disable_search'),
    'disable_search_threshold' => (int) $chosen_conf->get('disable_search_threshold'),
    'search_contains' => (bool) $chosen_conf->get('search_contains'),
    'placeholder_text_multiple' => new TranslatableMarkup($chosen_conf->get('placeholder_text_multiple')),
    'placeholder_text_single' => new TranslatableMarkup($chosen_conf->get('placeholder_text_single')),
    'no_results_text' => new TranslatableMarkup($chosen_conf->get('no_results_text')),
    'inherit_select_classes' => TRUE,
  );