Disable Comments Completely By Using Hook in WordPress ?

If you prefer to remove all comments manually from your site, you can paste the following code into the functions.php file of your child theme.

Here is the code snippet:

add_action('admin_init', function () {

    global $pagenow;

    if ($pagenow === 'edit-comments.php') {
        wp_safe_redirect(admin_url());
        exit;
    }

    // Remove comments metabox from dashboard
    remove_meta_box('dashboard_recent_comments', 'dashboard', 'normal');

    // Disable support for comments and trackbacks in post types
    foreach (get_post_types() as $post_type) {
        if (post_type_supports($post_type, 'comments')) {
        remove_post_type_support($post_type, 'comments');
        remove_post_type_support($post_type, 'trackbacks');
        }
    }
});

// Close comments on the front-end
add_filter('comments_open', '__return_false', 20, 2);
add_filter('pings_open', '__return_false', 20, 2);

// Hide existing comments
add_filter('comments_array', '__return_empty_array', 10, 2);

// Remove comments page in menu
add_action('admin_menu', function () {
remove_menu_page('edit-comments.php');
});

// Remove comments links from admin bar
add_action('init', function () {
    if (is_admin_bar_showing()) {
    remove_action('admin_bar_menu', 'wp_admin_bar_comments_menu', 60);
    }
});

Happy Coding ?