By “financial regulation” do you mean capital requirements being set by unknown individuals at the DTCC according to a formula that is unknown to the public and, by his own admission, even the CEO of Robinhood himself? I don’t know what I’d call that but it’s not what one typically thinks of as financial regulation.
The idea that UX/UI on a consumer oriented product like this is "superficial" seems bizarre to me.
Robinhood seems to people, however ignorant the impression may be, that they don't act like the Big Evil Wall Street Corp guys. So it's not unreasonable to use a good platform for analysis and use Robinhood to trade.
FYI: they will get a little testy if you have more than three round trips without registering as a day trader.