Display comment form without the comment thread
To display comment form without comments list, you need to override field--comment.html.twig template, and remove the following lines:

  {% if comments and not label_hidden %}
    {{ title_prefix }}
    &lt;h2{{ title_attributes.addClass(title_classes) }}&gt;{{ label }}&lt;/h2&gt;
    {{ title_suffix }}
  {% endif %}

  {{ comments }}


to override it:


From your theme, just create one of the following twig file in you templates folder, and put in it field--comment.html.twig content without the above section.




   * field--node--comment--article.html.twig
   * field--node--comment.html.twig
   * field--node--article.html.twig
   x field--comment.html.twig
   x field--comment.html.twig
   * field.html.twig



Note: the above suggestions for article content type, you may have different suggestions.


From your module, implement hook_theme for one of the suggestions like the following:




/**
 * Implements hook_theme().
 */
function MODULENAME_theme($existing, $type, $theme, $path) {
  return [
    'field__node__comment__article' => [
      'base hook' => 'field'
    ],
  ];
}



And make your changes in MODULENAME/templates/field--node--comment--article.html.twig