Custom taxonomy hide meta box but show in menu

_taxonomy.php

<?php
function cptui_register_my_taxes_region() {

	/**
	 * Taxonomy: Regions.
	 */

	$labels = array(
		"name" => __( "Regions", "twentyseventeen" ),
		"singular_name" => __( "Region", "twentyseventeen" ),
	);

	$args = array(
		"label" => __( "Regions", "twentyseventeen" ),
		"labels" => $labels,
		"public" => true,
		"hierarchical" => false,
		"label" => "Regions",
		"show_ui" => true,
		"show_in_menu" => true,
		"show_in_nav_menus" => true,
		"query_var" => true,
		"rewrite" => array( 'slug' => 'region', 'with_front' => true, ),
		"show_admin_column" => true,
		"show_in_rest" => false,
		"rest_base" => "",
		"show_in_quick_edit" => false,

		'meta_box_cb'       => false,
	);
	register_taxonomy( "region", array( "dealer" ), $args );
}

add_action( 'init', 'cptui_register_my_taxes_region' );

https://wordpress.stackexchange.com/questions/231125/custom-taxonomy-hide-meta-box-but-show-in-menu