I've been told who and what to cite in articles (even if it was only very tangentially relevant) as a Ph.D. student in HCI as far back as 2014. I also had to put my advisor as a co-author on papers that he didn't even bother to read...

I’ve never been a part of academia but I know it’s been fraught with all sorts of fraud for the last few decades (maybe forever idk) but this is a new type of weirdness to me. Is anything trustworthy is that space?

It's not really fraud though. If we get paid to upvote each other, the problem is not that we upvote each other but that there's someone paying us to do so.

same. I read through publications of my institute for my MS (EU, pretty big tech-focused university) and they pretty much also cite in circles (same institute and other related institutes of our university).

There are also ethnic/cultural circles as well (Chinese students come to us to study with Chinese professors who only cite other Chinese papers).