Doesn't this happen in pretty much any group ? The more what you say goes against the consensus, the more the group will reject it.

No, I don't think so. It certainly wasn't a thing that I was aware of prior to roughly two years ago. Maybe it's "normal" now but that's probably because certain people made you show your identity card in order to dissent.

I've noticed this trend where people started to accuse each other of psychological trickery a lot. I think it descends as a "defense" from that. I was never really sure of how many psychological games were really being played and how much people just reached for the terms to use as dismissal from criticism.

Yeah, if you believe the internet, "gaslighting" is something that people are trying to do to you all the time.