wp_rest_cache/allowed_endpoints does not work for me

On almost pure wordpress 5.8.2, simple code to test, but doesn’t activate the plugin = (

add_filter('wp_rest_cache/allowed_endpoints', function ($endpoints) {
    $endpoints['ahsle/v1'] = ['page'];
    return $endpoints;
}, 10, 1);
add_action('rest_api_init', function () {
	register_rest_route('ahsle/v1', '/page', [
		'methods' => 'POST',
		'callback' => function () {
			$posts = get_posts([
			  	'post_type' => 'page'
			]);
			return $posts;
		}
	]);
});

The standard wp rest api endpoints work as expected.
Why it happens?

Thanks for the plugin!