Same for me. A few days ago I got a 3 video countdown that if I don’t disable adblocking software that I would no longer be able to watch YT videos. After 3 videos I was blocked until I updated and restarted Brave. Now every video has the 5-10 second pause with the “Experiencing interruptions?” pop up.
I doubt it is exclusive to Brave. Just a cat and mouse game with Alphabet/YT as they are possibly about to take a big hit from the anti-trust lawsuit