Depends, do you want to save lives? Then self-driving cars only need to be a little safer than the drivers they replace. Which means if infrequent drivers with little experience that get replaced by robotaxis of average reliability could be a net-win in saved lives. Delaying their deployment until technology arrives that beats the most conservative drivers just means accepting a higher death toll.
I don't know if frequent drivers are inherently safer drivers than infrequent drivers. There might be the negative effect of reduced attention due to more 'routine'.
But I seriously doubt that frequent drivers drive so much safer that they negate the effect of being exposed to the risk so much more. Is a person that drives 10x more than the average driver more than 10x safer? Why replace cars first, that don't get on the street a lot? And how do you organize deploying SDCs to infrequent drivers first? Unless those people don't own the cars anymore, but rent them, in which case I agree. That would increase utilizations of these cars.
Yeah, that was the idea (hence robotaxis, not owned ones). It seems feasible especially in urban areas where car ownership is not essential so the remaining uses could be replaced by rented autonomous ones.
Personally I think the old joke about how 90% of drivers think they're better than average is both true, and also just a funny joke. We see a lot of perfectly good drivers on the road, but we don't notice them ... because they're perfectly good. There's only a few lanes on any given road, though, so if 10% of drivers in near proximity are crappy drivers then it practically shuts down the road. We notice that, and assume that most drivers are crap. Wrong.
However it frequently notices things before I do. Lane splitting motorcycles approaching for the rear for example. Or a car in front of me slowing down, but not using the brake lights.
It also does quite well when a car brakes in front of me, especially if it's a surprising slow down like on an onramp where I'm looking over my shoulder to merge.
So while I've not had an accident of any kind in over 25 years, I do appreciate the car noticing before I do.
So while I don't let the Tesla drive autonomously, I do feel like I'm a much safer driver with the active assistance from the car and that the Tesla (even with the same sensors) will continue to improve. Not sure if they will hit full autonmous on the current hardware, they might need another revision (to add CPU and better sensors) before they drive better than most humans.
The technology will certainly improve, however. Probably going to be quite a while, if ever, before I let it do all the driving, though :). At least partly because I enjoy driving.