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?
Yep, good addition and probably the really important one.
Personally I think they are going to find that the people who use add blockers will never view adds on youtube.
They will either find a workaround or stop using it all together.
If the publicity around this action causes more people to move in the direction of using addblockers it could be really counter productive for youtube.
That all depends on if the revenue loss from an increase in ablocker use is more than the revenue gain from people either disabling adblockers or purchasing a plan.