Change The Woocommerce Product Categories Dropdown Widget Placeholder Text

This worked for me:

add_filter( 'wp_dropdown_cats', function( $html, $args ) {
    if ( $args['taxonomy'] === 'product_cat' ) {
        $html = str_replace( '<select', '<select data-placeholder="New Placeholder"', $html );
    }
    return $html;
}, 10, 2);