Regarding what you wrote above:
I don’t really know what you mean by esoteric derivatives? Are you talking about single-stock options or various futures or ETNs or maybe VIX derivatives? FWIW, I think retail options trading isn’t great for almost anyone doing it, and I think people trade single stocks too much too. I think most ETFs/ETNs are ok but others might disagree about e.g. 3xS&P500 or whatever. There are other exceptions.
However these things aren’t new to robinhood. It’s been possible to trade those things (albeit without fireworks, and maybe with some kind of annying approval process) at plenty of discount brokerages for a long time. Crypto is a bit of an exception. Maybe there are other things one can trade at Robinhood and not elsewhere?
This isn’t about someone buying stocks more easily and cheaply this is about opening a complex leveraged position on some esoteric derivative that the 500 layers turned traders who came up with don’t even understand that can put you in the red for sums orders of magnitude larger than what you are investing in the first place.
We’ve learned the hard way that we need to limit the risk exposure of traders by both their experience and ability to take on losses and yes Robinhood cuts through that wall quite effectively.