> Can a single vehicle ever turn a profit?

That depends on how low they can get the costs. Waymo took delivery of the last Jaguar i-Pace, and are scaling up production of the Zeekr-based EVs, which I assume are significantly cheaper.

I think the math works, using car rental companies as an anchor point: they are (mostly) profitable*; they have relatively lower Cost of Revenue, I suspect Waymo will have much fatter margins.

* There was a blip when Hertz had to write-down its bold bet on EVs didn't quite work out.