No, it is because that is the content that people want to watch. I too create content that has been widely watched and don't include video ads or any of the other monetization features they push. But I create videos because I want people to watch them. I don't do it for the sake of myself and pushing it out into the void. I don't follow whatever the trends are, I create what I believe will be the most useful as I make educational content. And it works. But I post to YouTube because that is where people will find it.

If I were to self-host my videos or put it on PeerTube if I wanted anyone to see it I would actively have to go out and promote it myself. YouTube does that for me.