Most of the world's population doesn't drive a car because they can't afford one.
"I suspect the car is going out of fashion as people move more and more into dense cities."
Really? millions and millions of chinese people moved to massive urban areas and the first thing they buy when they earn some money is a car or a motorcycle, making China the biggest auto market in the world around 2010/11.
Pretty much the same pattern with the "BRIC"s
Look, everywhere outside the same old cosmopolitan places where the reality distortion field is too strong, people will own a car and they will make roads and bridges so they can happily drive them.