And you can’t just repave roads, there are utilities and sewer that needs to be moved, and that’s the small problem. The big problem is facing the outcry of very active voters for reducing their road space and making their commutes even a minute longer.
And if all the homes around this repaved area are detached homes with garages in 0.1+ acre lots, you will never have the density of customers to support businesses.
It kind of has to start at a city center and slowly, very slowly spread outward. But as soon as you hit the higher end suburbs with bigger plats, that’s where any of that high density hope stops, because the political will simply isn’t going to be there. Look at any US city and you will see the “trendy” or “hipster” or whatever areas with a few restaurants and whatever in a small walkable area are all in areas with postage stamp houses in tiny lots.
You don't have to redo sewers etc when you just change the surface by removing stroad space and adding bike lane space.
Also you can own a car and still bike to places.
Not really. Repave the roads to make them slimmer, use the space gained to provide elevated sidewalks and bike lanes so people can see it with their own eyes that they can now participate in traffic without sharing infrastructure with cars. And whenever a reasonable sized lot goes up for sale, buy it up and convert it to a small store.