I'm honestly amazed that anybody bought "pivot to self-driving cars" as a strategy. Even if it did work and they built perfect working autonomous vehicle software, right now, legitimately, what's the next step? Were they going to buy and operate a fleet? Have random people sign up to rent their unused cars out as taxis?
It's not problematic at all. But it would require Uber to cease being a software company and start being, like, an actual taxi service, with physical assets and vehicles and garages and maintenance. The whole reason Uber is competitive with actual taxi services is that those costs are all offloaded to the poor saps who drive for them.
That sort of thing is outsourcable... Just work with a manufacturer or a car rental company, they'd do the maintenance, and Uber would do the stolen, allegedly, software.
But they also don't have to pay the drivers at all. It's a pivot from making the drivers foot the bill but its not obviously untenable as a business model. I think the part that should raise eyebrows is Uber's claim they can actually build the cars before they run out of money.
They will have to change their entire organization, structure and how they do business, to accommodate this. It's as "easy" as copying Apple's vertically integrated model - many have tried...
They'll take that risk for one single day. Then they'll wake up the next morning with their vehicle, which they rented out to Uber for taxi rides overnight, parked in their driveway full of vomit. That's the best case scenario, where the box actually exists and works, and Uber can find a sucker.