What is ironic about it? There are already pedestrian-only zones in many cities, aren't there?
Ironically, the aim should be towards the opposite you're suggesting. By increasing the density and removing space between buildings, you are creating a city where it is more viable to use bikes or walking as your main mode of transportation. Subways are useless if your final destination isn't easily walkable from your stop. Your goal shouldn't be to create a city for cars, your goal should be to create a city where it is easy to get somewhere.
I do mostly agree with the three or four story height, though. This is the proper height to use for most suburb-style developments, higher is only really needed in the CBD.
Ironically, the aim should be towards the opposite you're suggesting. By increasing the density and removing space between buildings, you are creating a city where it is more viable to use bikes or walking as your main mode of transportation. Subways are useless if your final destination isn't easily walkable from your stop. Your goal shouldn't be to create a city for cars, your goal should be to create a city where it is easy to get somewhere.
I do mostly agree with the three or four story height, though. This is the proper height to use for most suburb-style developments, higher is only really needed in the CBD.