[wizofaus]

It's only not feasible because that's how the infrastructure and town planning in many urban areas has been done, and has somewhat succeeded because the degree to which you'll be dependent on a car to get everywhere isn't a super high priority for most when first choosing somewhere to live. The challenge is convincing governments and home buyers that the pros of less car-dependent cities massively outweigh the cons (which are mostly around accepting being closer to your neighbours and having less yard space/more stairs, plus governments having to focus on more than a single mode of transport when building roads etc).