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.
This is what the car lobby wants you to think. The transformation to a better and more livable city free from overwhelming car traffic is closer and faster than you imagine. The primary challenge is the power of the car-industrial complex both inside and outside government and the continued work to destroy and hobble other forms of transit.
The city I live in is modest in size, 250k-300k depending on who you ask. It will never be a walkable city. Throughout much of the year, that's asking to die of heatstroke or something. It will never have a subway. Hell, there's only one or two buildings that are more than 5 stories tall. It is hundreds of miles away from any city of comparable size. My in-laws live in a township of about 6000 an hour away.
Are we supposed to give up cars? I have a 6 minute ride to work in the morning if I hit the stop lights wrong. Why would I ride the piss-stinking bus, when it'd add 20 minutes of irritation to my day?
It's not a car-industrial complex that is an obstacle to your imagined utopia. It's that there are people like myself who don't want to make our lives more difficult so that yours gets better. I'd be shocked if there's a non-coastal city or town anywhere in North America that supports your vision.
It's enough that they don't make things worse for me specifically and spitefully. I do wonder why that wouldn't be good enough for you.