There's a couple misunderstandings here.

> The robotaxi can only compete on price because that's its only advantage.

That's one advantage. Another is that that it's a third option to the traditional dichotomy of driving yourself or be driven by a stranger.

It's worth taking a step back and looking at the bigger picture. Robotaxis aren't the end-all-be-all for anyone. It's just a bounded problem domain with some promise of commercial profitability on the road to "full autonomy". A baby step, in other words. Yeah, the autonomous vehicles on the road today aren't clearly and obviously better than the best human drivers, but how are they going to get to that point without going through all the intermediate steps to get there?