I think the tricky part is that at some level you want to be comparing counterfactuals. That is, accident rates of Teslas on autopilot with a driver of Tesla-driver abilities, in road conditions where the accidents occur, and so forth.

It kinda seems self evident that a car that drives you into a wall randomly is less safe than one that doesn't.

I grant that Teslas might be safer than eg a drunk driver, and so we might be better off replacing all cars with Teslas in some sense, but we'd also be better off if we replaced drunk drivers with sober ones. But would safe, competent drivers be safer, and would that be ethical? At that point are you penalizing safe competent drivers?

Drunk drivers in Teslas are actually interesting for me to think about, because I suspect they'd inappropriately disengage autopilot at nontrivial rates. I'm not sure what that says but it seems significant to me in thinking about issues. To me it maybe suggests autopilot should be used as a feature of last resort, like "turn this on if you're unable to drive safely and comply with driving laws." But then shouldn't you just not be behind the wheel, and find someone who can?