I have maintained the viewpoint for a while that if Uber's valuation is based on the inevitability of driverless cars and the reclaiming of that 80%+ revenue they are in trouble. Driverless cars even when the tech is ready will take many years to clear the political hurdles necessary for wide enough usage to help Uber. The same people that put Trump in office are not going to happily accept tech that will be painted in the political light as a tool to remove tens of thousands of jobs from the economy. The politics is going to be almost as big of a hurdle as the tech itself.

(Not to mention that removal of the driver opens up Uber's competition many competent tech companies with deep enough pockets and direct access to the masses.)