I've only noticed one change recently on YT where the imbedded video progress bar now can have sections. I wasn't aware of it before this week.

Newpipe, dl-youtube and so on still work, so I don't think there have been any major changes in html layout this year.

I've also seen the site hold up my adblock for several seconds at the start of a video, but it doesn't seem to be doing it right now.

Have you tried m.youtube.com instead?