I do agree generally to your position, but I'm not sure this is all there is to it. Let's say that these vehicles get really good at preventing crashes with jaywalkers. However, they have one weird quirk where every now and then they tend to jump the curb after misinterpreting the sidewalk as a shortcut. Even if the total number of deaths dropped, the population killed (people following the rules on the sidewalk) vs the population saved (people breaking the law) would change and we probably wouldn't accept the new balance.
If it turns out this woman was jaywalking at 10PM at night and the autonomous car acted reasonably, then of course we should let it off the hook (the same way we would any driver).