> There are many human failures which are distinctly a vision issue and not attention related

Which are a tiny minority. The largest causes of crashes in the US are attention/cognition problems, not vision problems. Most traffic systems in western countries (probably in others, too, but I don't have personal experience), and in particular the US, are designed to limit visibility problems and do so very effectively.

But how many of those crashes not caused by inattention could have been avoided with less idiocy and more defensive driving? I mean, yes, we can’t see as well in fog, but that’s why you should slow down