Be careful not to fall into the narrative the mainstream US media is selling, though it shifted drastically yesterday -- this is not a coordinated attack. WSB is full of people shilling all types of tickers for all types of reasons, but there is a large amount of people there who
understand (or at least pretend to) the dynamics of a gamma + short squeeze, and are in it for that reason.
The person who posted one of the earliest bull case research for this (referred to by his YT channel name RoaringKitty or his reddit username u/deepfuckingvalue) has been into GME since last year. He was holding LEAPs (long-dated call options) and shares and has been holding for the last year. He was ridiculed in the original post, because everyone still believed Gamestop was Blockbuster v2. Gamestop is not Blockbuster v2 (I used to think it was), but what's happening right now is not about fundamentals (and if you see anyone arguing that, they are trying to trick you by reframing), it is about the mechanics of a combination of a gamma and short squeeze happening at the same time.
Hedge funds do this kind of attack when they realize the opportunity is there -- you don't hear about it because it doesn't make the news, and because the news makes up a rationalization. Here's an example -- a bunch of stocks that were essentially left for dead (heavily shorted) popped yesterday and the rationalization was retail jumping in. That makes sense, unless you take a second and think about it -- how can the retail that's all still all-in on GME be simultaneously moving huge amounts of market cap of smaller companies? Yes those companies were cheap but they're cheap because they were shorted -- this means anyone could move them. Don't forget that ~90% of all stocks are owned by the top 30% or something like that. Retail can possibly cause gamma squeezes (see TSLA last year), but institutions have to take part for it to go anywhere.
It is 140% the fault of the short sellers that didn't take profit last year (assuming some rode GME from 45 to 5, this is a ~10x position If i understand correctly) that this short squeeze had the chance to happen. Greed got them.