Europe. When I lived in the US I saw cars with bald tires, clearly damaged frames, spewing insane amount of smoke &c. on the road daily, I'm glad I don't have to deal with that over here.
44 states have minimum tread depth specified in the law. Almost nobody has the tool necessary to replace a tire anyway, so nobody does that themselves. So what’s your point?
Not sure why you would assume that prohibiting people from working on their cars would increase the level of maintenance.
Not sure why you would assume that prohibiting people from working on their cars would increase the level of maintenance.