It’s not necessarily their activity though.

The algorithm will include one’s demographic, location, the things the people around you watch, and other things.

People ITT do seem to be taking “something about their activity” more harshly than it was meant. An innocuous video like fly fishing will lead to right wing content.

Fit me for a tinfoil hat, if you’d like, but I don’t think it’s just about what they think you want to watch. These services are controlled by right wing techbro nut jobs and use their platforms to proselytize.