I use youtube across different devices with the same account. sometimes, i even use it in multiple browser profiles or apps on the same device (with the account logged in).
the ad reminder got me. it actually stopped serving any youtube video on my laptop. so i made a new profile in firefox, logged in, and it was fine. for a couple days.
so i made a new profile, logged in, and... was foiled. but not to be deterred, i did what any reasonable person would do: i sought out one of the DOZENS of alternative frontends and used youtube's recommendation algorithm on the main site to pull videos from the alternative frontend.
for one day.
today, on my laptop, with my old profile, never changing logins or browser settings, youtube started working again.
did we win?
After I disabled all other adblocking related extensions besides uBlock, removed my custom rules and started updating the "quick fixes" filter list manually after every longer break from YouTube (+3 hours) I haven't had the popup since. Now I even have sponsor block and return dislikes enabled too and the popup still stays away.