I think you greatly underestimate seatbelt laws. Seatbelts were seen as bike helmets back then, almost nobody used them. For example, according to this study se

I think you greatly underestimate seatbelt laws. Seatbelts were seen as bike helmets back then, almost nobody used them. For example, according to this study setbelt laws increased seatbelt usage from 6% to 70% in just a few years. https://www.sciencedirect.com/science/article/abs/pii/000145758190021X https://www.sciencedirect.com/science/article/abs/pii/000145...