Does it really use watch history? I mean when it’s off, it still collects it, just doesn’t show it to me/publicly. I know that because sometimes people watched videos at my work pc and after that I had to clean up this mess.

I tried to turn it on for a while and it didn’t make any difference. Same for likes/dislikes. The only effective methods are channel-wise, i.e. “subscribe” and “don’t recommend channel”, but then the feed becomes 90% of videos I have watched or new videos (from these channels) in which I mostly have no interest in. Other 10% are irrelevant to me.

Anyway, I’ll try to follow your advice (thanks!) with more active liking etc for a while, but my hopes are weak atm.