That's not relevant because it doesn't change under a driverless system. Uber already gets "their" cut. The change is that Uber gains as costs what the driver

That's not relevant because it doesn't change under a driverless system. Uber already gets "their" cut. The change is that Uber gains as costs what the driver would have paid to own, maintain, and operate the vehicle, and gains as an income what it would have paid the driver. The "driver profit per mile" nicely factors those things together.