@aral I used Safari (with ad-blocker) yesterday for once to access YT and noticed the same. I use Sudeep Biswas' #Firefox add-on Alter and let any #YouTube link automatically filter through an #Invidious instance. No ads, everything loads quickly, no autoplay if not desired. I still need to test if that way music playlists can run uninterrupted.
Oh, and I live in the EU.