Recommending you a video you don't want to watch is a wasted opportunity. If you don't want to watch it, you won't, so YouTube's earnings are zero. If something you do want to watch is recommended instead, you will, and YouTube's earnings are nonzero.
I'm right now on a browser without my account and on which I don't usually watch YT, basically only when someone pastes a link while gaming. About half of the front page are things I might have clicked on when bored. A third are long. Two are definitely controversial. I don't buy your hypothesis.
Disclosure: I work in Google, but my closest contact with YouTube was drinking whisky with a YouTube SRE some four years ago.
I'm right now on a browser without my account and on which I don't usually watch YT, basically only when someone pastes a link while gaming. About half of the front page are things I might have clicked on when bored. A third are long. Two are definitely controversial. I don't buy your hypothesis.
Disclosure: I work in Google, but my closest contact with YouTube was drinking whisky with a YouTube SRE some four years ago.