In my experience they do affect the picture quality a tiny bit, but the sacrifice is balanced by not having a glare on the screen any more. What country are you in? If you have access to Amazon just try searching “Nintendo Switch matte screen protector”.

It will change the screen quality slightly, though I like to think of it as free anti-aliasing

Though here you go friend, I used their steamdeck protector, though I’ve linked the switch one