It's a classic tragedy of the commons. It's not easy to build such a city, even if everyone agreed that it would be better. It's difficult to get people to buy into a set of rules that would improve everyone's lives, if they think that somebody will be getting a bigger slice of the commons than they will.
It's even harder when there are people who devote their lives to making it harder. People will create Gish gallops of false information to instill fear, uncertainty, and doubt. Then they'll point to the lack of successes -- because the experiments you ask for never get done.
It takes a supreme act of will -- practically a benevolent dictator -- to get from here to there. There are places that are trying it, and the preliminary results are positive. Look at Paris and Barcelona, among others.
That doesn't mean you, personally, will like such a city life. But some people like what cities bring, and like that they are more energy-efficient than living elsewhere.