If I had to guess, I'd say it's a net positive. Robinhood is now all over the press at the cost of a lawsuit from a bunch of Redditors who allege Robinhood can manipulate the stock market.

Not sure I agree. The attention their shady business model is getting now is not something they would've liked. I'm also not sure what it means to their user growth. One one hand they are getting a lot of press which can help them gain more users. On the other hand, the press they are getting is not positive and their app ratings are going down (Google/Apple would likely give them some protection but they cannot block negative ratings forever). If many traders start migrating to other trading solutions it can have a snowball effect.