Remove gutenberg editor from custom post types #wordpress

disable-gutenberg-on-post-type.php

<?php

// Remove gutenberg editor from custom post types
function prefix_disable_gutenberg($current_status, $post_type)
{
    if (in_array($post_type, ['client'])) {
        return false;
    }
    return $current_status;
}
add_filter('use_block_editor_for_post_type', __NAMESPACE__ . '\\prefix_disable_gutenberg', 10, 2);