defaultDisplaySorts example

  protected function buildDisplayOptions($form, FormStateInterface $form_state) {
    // Display: Default     $display_options['default'] = $this->defaultDisplayOptions();
    $display_options['default'] += [
      'filters' => [],
      'sorts' => [],
    ];
    $display_options['default']['filters'] += $this->defaultDisplayFilters($form, $form_state);
    $display_options['default']['sorts'] += $this->defaultDisplaySorts($form, $form_state);

    // Display: Page     if (!$form_state->isValueEmpty(['page', 'create'])) {
      $display_options['page'] = $this->pageDisplayOptions($form, $form_state);

      // Display: Feed (attached to the page)       if (!$form_state->isValueEmpty(['page', 'feed'])) {
        $display_options['feed'] = $this->pageFeedDisplayOptions($form, $form_state);
      }
    }