A lot of the comments here are in the spirit of "just clear your history" or "just be careful about what you watch." If you have to go out of your way to step over eggshells in order to get good recommendations, that indicates the problem is with the designers and decision-makers instead.
Not only that, it's wrong. I can have zero "conspiracy" videos in my history/cookies and still sometimes see recommendations for it. Granted it was worse years ago.
I actually like conspiracy videos (for fun), but Youtube did something a few years back so that they are recommended with much less frequency.
Also to get a totally clean slate, which is still not perfect as you said, you have to delete subscriptions and likes as well as watch history. I've tried it a few times, but since I keep my subscriptions I always end up back on the same topics.
