At first, Data was sanitized [here][1] (line 2997).
If you don't want any plugin/theme run on action `save_post`. User `remove_all_actions` to remove all functions hooked to action `save_post`.

    function post_save_action($post_id, $post, $update)
     {
        if ($this->is_temp_saving_post($post, $post_id)) {
            return;
        }
        // Check user permissions
        if (!current_user_can('edit_post', $post_id))
            return;
        // Update post
        if (!$this->is_proper_post_type($post)) {
            return;
        }
        $processed_content = $this->process_post_data($post);
        $update_data = [
            self::POST_ID => $post_id,
            self::POST_CONTENT => $processed_content
        ];
        // Remove all functions which hooked to this action, to prevent run twice.
        remove_all_actions('save_post');
        // Update the post into the database
        wp_update_post($update_data);
        add_action('save_post', array($this, 'post_save_action'), 99);
     }



  [1]: https://developer.wordpress.org/reference/functions/wp_insert_post/