Fair enough, that all makes sense.

I just see "mass formation" as a re-wording of the already existing concept of "problem -> reaction -> solution". The "mass formation" is just the "reaction" part, where the reaction of the public is guided by the media to be as traumatic and deep and wide as possible, so everyone's desire for the solution is easily guided and everyone behaves similarly because they had the same reaction to the problem. If I really had to detail what's going on right now more deeply, I'd call it "short-term emotional shock driven mass idea formation" but I guess that's too many words.