At first, I implemented the uBlock Origin method, recommended by @salarua@sopuli.xyz, and it seemed to work at first.
Today, I got another Anti-Ad blocker message and decided to try the method described by @Peekystar@kbin.social and, again, this seemed to work at first.
Later today, neither of these methods work when trying to use YouTube itself. The redirect methods, probably, work fine if you are NOT using YouTube itself.
I am running Duck Duck Go Privacy Essentials and uBlock Origin on Firefox. I don't get ads or the message on any device (2 windows laptops, a Linux laptop, windows NUC) and I am logged in to youtube/google accounts on all of them. Don't know if I've found some magic formula or have just been lucky, but I keep forgetting google's trying to pull this shit until I run across posts like this talking about it...
I am curious about this too. I do not see ads and all I have is Firefox configured rather strictly and uBlock Origin configured strictly as well. I never login though.