ACF | Post Types & jetpack_sitemap_post_types

$ cat custom-jetpack-sitemap-20250317.php
<?php
/*
Plugin Name: Dynamic Post Types in Jetpack Sitemap (MU)
Description: Dynamically includes all registered public post types (including ACF types) in the Jetpack XML sitemap.
Version: 1.4
Author: ChatGPT
*/

if ( ! defined( 'ABSPATH' ) ) {
    exit; // Exit if accessed directly.
}

/**
 * Get all registered public post types for Jetpack sitemap.
 *
 * @return array List of valid public post types.
 */
function get_dynamic_sitemap_post_types() {
    static $cached_types = null;
    if ( is_null( $cached_types ) ) {
        $excluded_post_types = ['attachment', 'revision', 'nav_menu_item'];
        $all_post_types = get_post_types(['public' => true], 'names');
        $cached_types = array_diff($all_post_types, $excluded_post_types);
    }
    return $cached_types;
}

/**
 * Add public post types to Jetpack sitemap.
 *
 * @param array $post_types Existing post types in the sitemap.
 * @return array Modified list of post types.
 */
function dynamic_jetpack_sitemap_post_types( $post_types ) {
    return array_unique(array_merge($post_types, get_dynamic_sitemap_post_types()));
}

/**
 * Hook into Jetpack sitemap filter once plugins are fully loaded.
 */
add_action('plugins_loaded', function() {
    if ( class_exists( 'Jetpack' ) && method_exists( 'Jetpack', 'is_module_active' ) && Jetpack::is_module_active( 'sitemaps' ) ) {
        add_filter( 'jetpack_sitemap_post_types', 'dynamic_jetpack_sitemap_post_types' );
    }
});
$

REF:

• ACF | Post Types and Taxonomies
• jetpack_sitemap_post_types – Jetpack Developer Resources