I like my recommendations not coming from my subscriptions. I check my subscriptions for new stuff often, so I want the recommendations to be other stuff.
But you're right, they outright sucks. They are definitely dynamic because I only have to show my son a single Roblox video to change it, but at the same times there are stuff that is repeatedly showing up that I have no interest in. Even stuff that I've told YouTube that I'm in no way interested in...
What I REALLY miss is a random category - for stuff that I would never otherwise see.