Dequeue styles unless is_single

Hi guys
The ytprefs.min.css (and various other files) all load on every single page – regardless of whether there’s a video or not.
I’ve tried to dequeue via the following:

if( ! is_single()  ) {
	wp_dequeue_script('__ytprefs__');
	wp_dequeue_script('__ytprefsfitvids__');
	wp_dequeue_style('__EPYT__style');
	wp_dequeue_style('epytgb-style-css');
}

but have so far had no luck – the stuff still loads on every single page.

Appreciate they’re lightweight, but still – is it possible?