Okay, so in the extreme case Uber's self driving division is estimated to be worth ~$7 billion? That proves my point more than it refutes it. Their stock has fluctuated more than that this past month.
The developing narrative seems to be that self-driving was a longshot that could have paid off hugely, had it worked out, but it's been plagued with problems and it just seems very unlikely to pay off now. But still not zero, since no one else has shipped anything.
Investors probably valued it like (0.7% chance of success * 1 trillion upside = 7 billion).