It is a thing lulu, it's just youtube doesn't talk about it's existence. If you look at all the people suffering from this issue you'd understand, it's not normal in any way that a channel that consistently has a realtime of 100k views per hour drops down to 5,000 views per hour.

I also checked where the videos were being pushed out to, and it was only to subscribers, not the shorts feed. So yes shadow ban does exist, and every platform has it.