The drivers are going to be removed from the equation no matter what though.
Uber just needs to think of themselves as a mobile staffing company and they'll be fine. Unfortunately, staffing is a market where "Move fast and be an asshole" isn't a great philosophy so they'll need a bit of a temperament change to survive.
This would basically turn them into a private driver service and finding qualified staff would be a pain for anyone wanting a french tutor for the drive. Ignoring that as an off the wall example though they'll still hit a pretty hard wall with trust. Even if the fear is unfounded trying to get a huge number of people to sign up for random (to them) people to pick up and drive around their kids is running into a lot of child abduction/abuse fears that run kind of deep in the US.
Why? Just filter on the "Speaks French" tag.
Are you trying to argue that there is zero use for a person with a car who speaks French in a city like San Francisco? I really don't understand what you're trying to convince me.