I’m under the impression that Google deliberately hinders their YouTube platform just because you have ad-blockers. With videos taking time to buffer, seems to signal this, because it almost makes up nearly the amount of time for when ads take if you had to watch them. So since you’re ad-blocking and they don’t like that, they’ll make your experience miserable until you want to pay their service or not use ad-block.
People really do not like to be reminded that the only thing that separates us from animals is our ability to save information.
Seriously, it all comes down to collective knowledge.