I don't think this is true at all. Most of the world population lives in third world conditions. They may not have a car, because they can't afford it, but that

I don't think this is true at all. Most of the world population lives in third world conditions. They may not have a car, because they can't afford it, but that doesn't mean their neighborhoods are "walkable". Visit the slums of Mumbai, or the shanty towns of Lagos, or the favelas of Lima. These may be high density, but they're certainly not "walkable". Either in the sense of being pedestrian friendly or having many services easily accessible by walking/public transport. There's a reason that the motorbike is one of the most popular consumer products for middle income countries. In the vast majority of the third world, the populace is desperate for any sort of personal motor transportation.