They were always there, but the impetus for frictionless experiences to drive revenue also removed all the barriers and effort to congregating and often exploiting those people.

It was there on Usenet, it's been there since people were scratching messages on bathroom stalls and subway walls.

But yes, now we have effectively created cult generators and not only does no one want to turn them off, really smart people (even many with good intentions) keep making them more efficient.