I stayed in a motel recently that had a kitchenette with a mini fridge in the same room as the bed. You can tell management spent extra for this fridge too, since it had a temperature readout and a see-through door. But by god, that bright blue LED temperature display lit up the entire room and kept me up all night. I tried to cover it with some paper, but that only made it spread further. A couple socks draped over the top eventually did the trick.
My understanding was that these programs don’t rely on YouTube’s API, but rather they are loading the page and scraping it for the relevant video files, comments, and other data. So it’s a little harder to kill them than just shutting down API access. That said, with all the new web DRM crap getting pushed by Google and others, I can’t imagine it will be long before they can detect that you aren’t viewing the page the way they want you to view the page, and then block access in some other form.