Trades of index mutual funds and ETFs held in the administrator’s brokerage were free for years before RH. (Eg, Vanguard funds at Vanguard and Fidelity funds at Fidelity.) What RH accelerated was $0 individual stock trades, which are not great for retail investors at any price.
Meanwhile wealthfront is marking up investment opportunities that are widely available in funds or etfs for much cheaper.
I think wealthfront is much more predatory than Robinhood if judged on the basis of services rendered to informed actors.