uBlock Origin as far as I can tell has been winning the race. As long as you stay up to date and clear the cache now and then. I've had one occasion (recently) where I got some ads which was fixed by updating uBlock origin, but maybe I'm not in Youtube's anti-adblock cohort.

When they first started this, a month ago (or so?) I just right-clicked and used block element with uBlock Origin to block the popup and the div element that covered the page to dim it.

I've not seen it since. Only side effect is videos sometimes pause right as they start. I assume because it stops the video and shows the pop up. I can just resume immediately though.