I run firefox with uBlock Origin (default settings) and Privacy Possum
When first saw the popup I was able to click thru and refresh to get past it.
Then a few days later that stopped working.
So I moved to using FreeTube an open source desktop youtube client. That worked (still works)
Then I noticed on youtube.com, that I could get through again with a refresh or two.
So it appears they are experimenting with different techniques.
I created a second account and so far I've not gotten that popup, but then again, it hasn't appeared in recent days when I use my old account either. So yeah, YT is definitely experimenting, trying to find the best way to make our experience difficult.