But the average hour is not driven by the average driver, better drivers drive more hours, so it has to be better than the average driver in order to result in fewer incidents.

There’s no reason better drivers drive more hours. You can be a shit semi driver. That being said, it’s an irrelevant comment. If it’s at average now this is the worst it can get and it’s already way above average.

I don’t disagree that self driving is good and will eventually get there. Just pointing out a flaw in your reasoning.

Yes, such a person can exist, the hypothetical counter example doesn’t disprove the general statement. I think it’s safe to say that in general the more time someone spends driving the better driver they are.