The Social Medias, how does they work?

Why am I getting alerts for new YouTube videos in iPhone that I am not subscribed to? I get alerts for subscriptions, but why am I getting alerts for channels that I’ve watched but not subscribed?

To be clear this is the YouTube app alerting my phone (and other Mac related things).

YouTube is one of a select few apps which have earned the “never notify my about anything ever, you ass” setting on my phone.

They do that to push content following. Besides your subs, it is based on channels you’ve watched but no subbed to. I get them a lot right up until the time I disable all notifications from YouTube entirely, like @inactive_user.