In my opinion self driving cars are a shiny object to distract VC's from Uber's massive operating losses. When they start making money with self-driving cars on a large scale then I'll take notice.
The landscape of the future is car manufacturers offering their own "Uber" like service and that service replacing the traditional ownership model. That doesn't mean Uber doesn't have a place before then though. Like good little capitalists, the VC's will cash out and make a ton of money while the real innovation and lasting impact happens elsewhere. So, yeah, Uber should blow up when self-driving cars become a thing but they'll eventually fade away. Unfortunately, that won't be for a long time.
EDIT: Oh, and yeah, people are also going to still be buying a shitload still anyway.
Expect an even bigger fund raise where they hope some other idiots, with even deeper pockets, will keep picking up the tab.