This is the aspect that makes me most excited about Waymo and the like –the prospect of no longer having to tolerate terrible driving because removing someone's license is akin to an economic death sentence. Fully commercialized, self-driving should provide an economic alternative to humans driving themselves. And we should be able to leverage that to stop the worst drivers ever getting behind the wheel again.
Wait, how is offering driver less cabs penalizing all drivers?
The only motivation I see that drives self-driving taxi development is reduced labor costs. But that isn't different than what has happened since the industrial revolution.