I also largely disagree with this "carless world" argument that seems so popular with young journalists living in dense, poorly-designed, and poorly-managed metropoli.
Every time these urban development subjects comes up on HN, I point at the Japanese examples of Tokyo and Osaka. Clean streets and sidewalks, pedestrians and bikes are everywhere, low rate of fatalities....and yet cars are everywhere too, and Tokyo has one of the most vibrant "car cultures" on the planet. So obviously we don't HAVE to get rid of cars to make a city of 10 million people function correctly.
The Japanese accomplish it via: 1) almost no curbside parking for POVs 2) commonly available yet expensive parking lots, with extremely narrow parking spaces 3) exorbitant vehicular taxes & registration 4) world-class public transit so the "plebs" are discouraged from needing a POV in the first place. Not having half of their population overweight or obese is probably also a factor (smaller vehicles which can take advantage of smaller parking spots, and fit people are probably more willing to walk/bike/etc.)
I DO like that the author covered how reducing road traffic is good for car enthusiasts too, and I very much agree: please give inattentive commuters who are hating life driving from Point A to Point B superior transit options.
As an aside, I visited NYC about a year ago with my Japanese significant other....the subway infrastructure is so archaic I felt embarrassed for our nation.