Cars are by now a hard to reverse environmental and urban planning disaster across the world. We are stuck with them. As a mode of transport it has grown uncontrollably at the expense of all others (except the airplane) and practically everything has been shaped to accomodate it.
Reversing that development, limiting car traffic to where its really needed is like trying to perform a complete heart and arteries transplant on a living person. Even if there was a will (which there is not) it is not clear if there is a way.
In the best scenario it will be an excruciatingly long transformation (~50 yr) as car oriented cities (or city sections) get slowly deprecated and the car-free or car-lite segments become more desirable, more livable.
Nonsense.
Ljubljana went from full of cars downtown to a 1 square mile pedestrian area with zero cars. It’s fantastic. And all the major arteries into the city went from 2 lanes to 1 lane + bus.
Amsterdam famously reversed its car centric design in the 1980’s.
Even San Francisco was able to close its main city artery to car traffic and transform many of the big roads with dedicated bus and bike lanes.
And those are just the cities I know about. There’s bound to be more. The feat is completely possible, but takes a while as any large refactoring does.
Or closer to NA have a look at Vancouver. From a high level looking at the whole region, it's about as devoted to cars as everywhere else in North America, though if you peek down to the neighbourhood level you can see some incredible successes in moving people away from car use. In the near downtown West End area for example, some 45% of the population walks to work.