Same experience here. It used to give me spot-on recommendations based on my watch history-often out of nowhere, but still accurate. That was one of the reasons I subscribed to YouTube Premium.

Now, I strongly feel it's based on a wrongly inferred social graph. It recommends videos according to what's happen in the group. It's really unsettling.

I wish there were a setting to disable this "feature." and to stick on my history.