Member of WSB here, no expert

The narrative of GME has been building for weeks before any news coverage happened. This isn't the first stock to blow up from WSB, but there are a few others in past weeks (none that have reached GME levels) such as BB, PLTR, and previously ABNB (whatever new stock that has IPO'd).

There are a handful of users that have $1M positions (some smaller ones, like a user that reported $250k into $7M, back down to $4.2M). Collectively, the community appears to drive hype towards different stocks based on flimsy things.

Without a doubt there's HFT (High frequency trading) happening, but these social communities are having an impact.