Force Site to use ACF to Function (MU-Plugin)

acf-required.php

<?php

! defined('ABSPATH') && exit;

add_action('plugins_loaded', function () {
    if (// is network install and main site is not set up
        (is_multisite() && ! get_blog_option(1, 'siteurl'))
        // is single site install and site is not set up
        || (! is_multisite() && ! is_blog_installed())
        // ACF is already installed
        || class_exists('ACF')
        // is WP CLI
        || (defined('WP_CLI') && WP_CLI)
    ) {
        return;
    }

    $notice = 'ACF is required for this site to function properly. Please install and activate the plugin.';

    // should die unless user is admin or on login page
    if (! current_user_can('install_plugins') && ! is_login()) {
        wp_die($notice);
    }

    add_action('admin_notices', function () {
        echo sprintf(
            '<div class="notice notice-error"><p>%s</p></div>',
            $notice
        );
    });
});