Disable default tags, emojis and resources in WordPress via functions.php

functions.php

<?php
/**
 * Disable Emojis
 */
remove_action('admin_print_styles', 'print_emoji_styles');
remove_action('wp_head', 'print_emoji_detection_script', 7);
remove_action('admin_print_scripts', 'print_emoji_detection_script');
remove_action('wp_print_styles', 'print_emoji_styles');
remove_filter('wp_mail', 'wp_staticize_emoji_for_email');
remove_filter('the_content_feed', 'wp_staticize_emoji');
remove_filter('comment_text_rss', 'wp_staticize_emoji');

/**
 * Disable XML-RPC.php
 */
add_filter('xmlrpc_enabled', '__return_false');
function remove_x_pingback($headers)
{
    unset($headers['X-Pingback']);
    return $headers;
}
add_filter('wp_headers', 'remove_x_pingback');

/**
 * Disable unnecessary tags
 */
remove_action('wp_head', 'rsd_link');
remove_action('wp_head', 'wlwmanifest_link');
remove_action('wp_head', 'wp_shortlink_wp_head', 10, 0);
remove_action('wp_head', 'wp_resource_hints', 2);
add_filter('feed_links_show_comments_feed', '__return_false');
remove_action('wp_head', 'wp_generator');
remove_action('the_generator', 'dt_remove_wpversion');

/**
 * Disable resources
 */
function disable_resources()
{
    wp_dequeue_script('wp-embed');
}
add_action('wp_footer', 'disable_resources');

/*
 * Disable JSON API
 */
remove_action('wp_head', 'rest_output_link_wp_head');
remove_action('wp_head', 'wp_oembed_add_discovery_links');
remove_action('template_redirect', 'rest_output_link_header', 11, 0);