Seems I was wrong. However, the Robotaxi fleet is still tiny compared to Waymo's. Jalopnik said the fleet was only 34 cars as of EOY 2025[0]. Waymo had over 2,000 as of September 2025[1].
Elsewhere in this discussion someone pointed out that each Tesla robotaxi in Austin is being directly followed by a supervisor in another car. That resource constraint could explain the low number.
[0]: https://www.jalopnik.com/2063124/tesla-austin-robotaxi-fleet...
[1]: https://www.automotiveworld.com/articles/waymo-confirms-flee...