Remove WooCommerce styles and scripts.

remove-woocommerce-styles-scripts.php

<?php
//* Do NOT include the opening php tag shown above. Copy the code shown below into functions.php

/**
 * Manage WooCommerce styles and scripts.
 */
function grd_woocommerce_script_cleaner() {
	
	// Remove the generator tag
	remove_action( 'wp_head', array( $GLOBALS['woocommerce'], 'generator' ) );

	// Unless we're in the store, remove all the cruft!
	if ( ! is_woocommerce() && ! is_cart() && ! is_checkout() ) {
		wp_dequeue_style( 'woocommerce_frontend_styles' );
		wp_dequeue_style( 'woocommerce-general');
		wp_dequeue_style( 'woocommerce-layout' );
		wp_dequeue_style( 'woocommerce-smallscreen' );
		wp_dequeue_style( 'woocommerce_fancybox_styles' );
		wp_dequeue_style( 'woocommerce_chosen_styles' );
		wp_dequeue_style( 'woocommerce_prettyPhoto_css' );
		wp_dequeue_script( 'selectWoo' );
		wp_deregister_script( 'selectWoo' );
		wp_dequeue_script( 'wc-add-payment-method' );
		wp_dequeue_script( 'wc-lost-password' );
		wp_dequeue_script( 'wc_price_slider' );
		wp_dequeue_script( 'wc-single-product' );
		wp_dequeue_script( 'wc-add-to-cart' );
		wp_dequeue_script( 'wc-cart-fragments' );
		wp_dequeue_script( 'wc-credit-card-form' );
		wp_dequeue_script( 'wc-checkout' );
		wp_dequeue_script( 'wc-add-to-cart-variation' );
		wp_dequeue_script( 'wc-single-product' );
		wp_dequeue_script( 'wc-cart' );
		wp_dequeue_script( 'wc-chosen' );
		wp_dequeue_script( 'woocommerce' );
		wp_dequeue_script( 'prettyPhoto' );
		wp_dequeue_script( 'prettyPhoto-init' );
		wp_dequeue_script( 'jquery-blockui' );
		wp_dequeue_script( 'jquery-placeholder' );
		wp_dequeue_script( 'jquery-payment' );
		wp_dequeue_script( 'fancybox' );
		wp_dequeue_script( 'jqueryui' );
	}
}
add_action( 'wp_enqueue_scripts', 'grd_woocommerce_script_cleaner', 99 );

Not working with WooCommerce 2.6.4

I removed right now some css files using this:

function woocommerce_dequeue_styles( $enqueue_styles ) {
    if ( !is_woocommerce() && !is_cart() && !is_checkout() ) {
        unset( $enqueue_styles['woocommerce-general'] );
        unset( $enqueue_styles['woocommerce-layout'] );
        unset( $enqueue_styles['woocommerce-smallscreen'] );
    }
    return $enqueue_styles;
}
add_filter( 'woocommerce_enqueue_styles', 'woocommerce_dequeue_styles' );

Is in documentation, check it out.

FWIW the WP 5+ Gutenberg block CSS handle is 'wc-block-style'

littlepackage

FWIW the WP 5+ Gutenberg block CSS handle is
twentysixteen-block-style

add_filter( 'woocommerce_enqueue_styles', '__return_empty_array' );