Each one of those bans can be explained as WSB being a victim of their own success. None of these companies have a compromising financial connection to Melvin Capital in the same way that Robinhood did.

For example, the WSB Discord was basically such a trainwreck that the WSB mod team themselves admitted they had significant problems keeping it under control. We can extrapolate that to Facebook as well. Hell, the WSB mod team even locked /r/WSB for a few hours to try and figure out a moderation plan. Most online platforms either rely heavily on community moderation (Discord, Reddit) or a small army of employee moderators that have to be rotated out frequently for the sake of their own mental health. Neither of these models work well for an already-rowdy community suddenly 10xing themselves in both scale and frequency of rules violations. It's basically uncontrollable and the only option is to shut it all down until you have a chance to cool off. (Again, that's why /r/WSB was locked yesterday.)

As for Google, they took a third approach: heavy automation. They have shittons of antispam systems specifically targeted to prevent review spamming. A sudden burst of 100k negative reviews from legitimate users angry that they can no longer participate in a financial flash mob is technically indistinguishable from someone who bought and compromised 100k accounts and decided to threaten Robinhood with negative reviews. Your antispam system isn't going to understand context (e.g. Robinhood fixing the books in a particular direction) but it is going to understand timing.

There isn't really a good way to handle this. The null option of "do nothing and let the problem fester" isn't a good option. This is because people will figure out that WSB is the server/subreddit/group you go on in order to break the rules and get away with it. Anyone with a chip on their shoulder about platforms having any sort of moderation rules will deliberately spam these corners of it, and normal people will assume that such behavior is now OK because there's no enforcement. This will spill over into other corners of the platform until everything is as bad as the lowest common denominator. (See also: what happens to subreddits as they grow, the entirety of 4chan, etc)