Unregister Widget Areas in Admin

admin-widget-areas.php

/* 
 * Comment out the ones you want to keep. You will need some, but not all, for each project. 
 * Also, if you un-register then you can't use the_widget();
 */

add_action( 'widgets_init', 'cab_unregister_widgets', 10 );
/**
 * Unregister Various Widgets
 * Clean up your widgets.php page
 * Single comment out the ones you want to keep
 */
function cab_unregister_widgets() {
    $unregister_widgets = array(
        'WP_Widget_Calendar',
        'WP_Widget_Archives',
        'WP_Widget_Tag_Cloud',
        'WP_Widget_Media_Audio',
        'WP_Widget_Media_Video',
        'WP_Widget_Media_Image',
        'WP_Widget_Media_Gallery',
        'WP_Widget_Meta',
        'WP_Widget_Categories',
        'WP_Widget_Recent_Posts',
        'WP_Widget_Recent_Comments',
        'WP_Widget_RSS',
        'WP_Widget_Pages',
        'WP_Widget_Custom_HTML',
        'WP_Nav_Menu_Widget',
        'WP_Widget_Text',
        'WP_Widget_Search',

        // * --- Genesis ---

        'Genesis_Featured_Page',
        'Genesis_Featured_Posts',
        'Genesis_User_Profile_Widget',

        // * --- WooCommerce ---

        'WC_Widget_Layered_Nav_Filters',
        'WC_Widget_Cart',
        'WC_Widget_Layered_Nav',
        'WC_Widget_Price_Filter',
        'WC_Widget_Product_Categories',
        'WC_Widget_Product_Tag_Cloud',
        'WC_Widget_Products',
        'WC_Widget_Rating_Filter',
        'WC_Widget_Recent_Reviews',
        'WC_Widget_Recently_Viewed',
        'WC_Widget_Top_Rated_Products',
        'WC_Widget_Product_Search',
    );
    
    foreach($unregister_widgets as $w):
        
        unregister_widget($w);
        
    endforeach;
}