I think you hit the nail on the head: instead of large, sprawling suburban cities built around the car, the US will need to rebuild cities around humans who walk and take bikes.
Completing the automation of agriculture is the only thing that would drive a significant fraction of the rural fifth into cities, and rebuilding suburbia to be denser is fighting against market trends. I'm betting we get self driving cars first, and I'm not at all sure I disagree with the article's title.