There is a reasonable argument to be made that whatever minute price slippage customers might experience(which I believe isn't even supposed to be legal due to NBBO and Reg NMS? not an expert) due to payment for order flow is much less than the $10 commissions at deep discount retail brokerages and certainly than the $50 trades in the old days of calling up your friendly local rent seeking broker -- for typical robinhood sized equity transactions.
Robinhood has plenty of problems but they directly caused investors to be able to trade for free @ fidelity, vanguard, schwab, etc which is obviously a boon to consumers.
Also imo at least robinhood is somewhat up front about like 'the market is a zany gambling game' with their UX. Contrast with IBKR and TOS who heavily market their stuff to Serious Portfolio Dads With 4 Monitors and then ALSO do sheisty manipulation appearing stuff to "protect their clients from volatility." RH targeting a smaller computer and being colorful doesn't make it any worse than other discount retail brokerages shoving derivative trading platforms at unsophisticated retail.