How to stop Elementor Templates appearing in WP Sitemap

I removed them by adding the following code to functions.php:

/* Remove elementor library templates from WP Sitemap */
add_filter(
    'wp_sitemaps_post_types',
    function( $post_types ) {
        unset( $post_types['elementor_library'] );
        return $post_types;
    }
);

Personally, I would like them to be excluded by default by the Elementor plugin itself.

@arinargubi The change to sitemap_index.xml is immediate.

The update to Google obviously would be when it next crawls your website. You could submit the sitemap again to Google Search Console to perhaps encourage a faster update.