I don't know if automobiles really are the test case, but there's a way of saying they are. It goes like this:
Culturally-speaking, and therefore in actual practice too, Chinese are not good at providing individual support for impersonal group benefits. If the group is not family, classmates or some other guanxi cohort, Chinese will not act to support the good of that group. Indeed, they may act to undermine any benefits that could have accrued to that group.
For example, the group is "road users" and the good of all - the safe, secure, prompt passage of all from their starting points to their destinations - is determined by an impersonal set of "rules of the road". Keep to your lane, keep to the speed limit, use indicators, give way, follow directions, wait your turn, and so on.
If given, say, another five to ten years of consumer car life and infrastructure provision, road use does not improve or indeed the death toll starts becoming war-like, well then we'll know.