Hides all Yoast premium nags in the backend

disable-yoast-nags.php

<?php
/**
 * Plugin Name: Disable Yoast Nags
 * Description: Hides all Yoast premium nags in the backend.
 * Version:     1.0
 * Author:      Zachary Scott
 */

namespace zacscott;

/**
 * Disables Yoast premium nags in the WP backend.
 *
 * @author Zachary Scott <zscott.dev@thecode.co>
 */
class DisableYoastNags {

	function __construct() {

		add_action( 'admin_init', array( $this, 'filter_admin_notices' ) );

	}

	function filter_admin_notices() {

		global $wp_filter;

		foreach ( $wp_filter[ 'admin_notices' ] as $id => $hooks ) {
			foreach ( $hooks as $hook ) {
				if ( !isset( $hook[ 'function' ] ) ) continue;
				$callback = $hook[ 'function' ];

				// Yoast free license nag
				if ( is_array( $callback ) && ( $callback[0] instanceof \Yoast_Plugin_License_Manager ) ) {
					remove_action( 'admin_notices', $callback );
				}

			}
		}

	}

}

// Boot
new DisableYoastNags();