It all goes back to zoning laws and regulations.
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I hate to even sound like this, I hate the cynicism in my comment, and maybe the answer is to actually just do it and not declare premature defeat, but having watched how other initiatives in my own local area have gone I can't help but feel that we don't have the real secret weapon that works for places like Japan, and makes stuff like Star Trek work outside of all the fancy tech, and that's sufficiently advanced culture to not immediately race this all to the bottom.
The locality will plan where their high-rise/commercial district is, houses on side-streets are can all be triplexes with an option for a low-impact business as in the article, and secondary streets have dedicated businesses.
As an area's population grows the federal zoning allows that bigger buildings can be built - small apartment buildings instead of houses, etc. The locals can't pull-up the ladder behind them and say "no new houses", locking out young people and renters and transplants.
I assume that the problem in the US is more regulatory capture than culture. Starbucks doesn't want you to be able to sell coffee to your neighbors. And your neighbors don't want more housing to be built, because it might affect their home values. I've seen how home owners adamantly oppose these things.
And for decades we've been left with most new housing being built by developers as cheap as possible - clear cutting some space on the outskirts of town and throwing together cookie cutter houses, car dependent and without much of anywhere nearby to socialize. It's a shame that in a country of 330+ million people there's not more variance.