I don't know to what extent that is true, I'm not saying it's not, but I also wonder. Having been in a lot of places where the traffic is unpredictable, I've noticed that people pay a lot more attention to the road and their surroundings and in general drive more defensively than on places where there is an assumption that everyone is following the same rules. This is just anecdotal of course, but I think it would be interesting to look into. I certainly feel a lot safer as a pedestrian in Mexico than in the US for example, even though the traffic is more unpredictable. But again it might be an illusion.