Probably because our odds of dying in a car crash are still something like 1/10,000. It's remote enough to not seem real.
> Your odds of dying in a car crash, over the span of your entire life, are somewhere in between 1 and 50 and 1 and 100. — http://www.asktheodds.com/death/car-crash-odds/
> Chance of dying in transportation accidents (mostly motor vehicles): 12 per 10k per year — https://www.livescience.com/
> Lifetime odds of death by motor vehicle crash, United States, 2016: 1 in 102 — http://injuryfacts.nsc.org/all-injuries/preventable-death-ov...
If you don’t know anyone killed in a car accident, you are very lucky.
If you only drive sober, always wear a seatbelt, and only drive cars with the highest NHTSA ratings then your lifetime chances are probably more like 1 in 300, if not less.
That said, your chances of getting seriously injured in a car crash are significantly greater than that.
Don't apply stats like this to yourself, use them to guide policy instead.
Otherwise cities like NYC would have a really low rate since so many people don't have cars.
Measure the thing you actually care about. After issuing metal helmets to infantry in WW1 the number of men hospitalised with head injuries climbed enormously. Were helmets a bad idea? Nope. To get hospitalised first you need to survive your injuries.
Miles driven would be useful too but not as directly useful in evaluating odds of any one random person dying in a car crash.
Regardless, I'm be interested in seeing the stats broken down by accident type (which is tracked by the police and insurance companies to some extent).
My suspicion is that there's several accident modes that are more common in North America that make up most of the difference.
I also suspect that just like pretty much ever other thing that's common at scale but statistically unlikely at the individual level socioeconomic status is the best predictor.