What’s the root cause? Cynical answer: Humans. Slightly less cynical: Cars. We've built an environment (in the US, at least) where driving a car is basically

What’s the root cause? Cynical answer: Humans. Slightly less cynical: Cars. We've built an environment (in the US, at least) where driving a car is basically a requirement to participate in society. So, people drive, whether they want to or not. And they drive whether they're physically or mentally capable of doing so successfully. And we're so entrenched in this design that discussion of a change is met with derision and scorn.