Some small fraction of that, actually. Drivers were willing to work for that amount of money, and customers were willing to pay. If you mandated that they be paid something on top of that, the buyers can compensate buy paying less for the "base". Since the drivers were happy with the previous take-home, they'll be happy with the new "minus base plus mandated benefits".

This is the problem with people casually suggesting that workers would be better off with mandated benefit x, y, or z. As long as Uber can still cut their portion, it can even out. (Or worse, if workers value the benefit less than the equivalent cash.)

See the concept of tax incidence: just because someone is charged more, doesn't mean any specific factor has a different take-home. https://en.wikipedia.org/wiki/Tax_incidence

"Uber has saved $730m by classifying drivers as independent contractors."