> something more like building Parisian boulevards, walkable, tree-line streets, and parks and such. Maybe even a train or bike lane.

I've often wondered why a billionaire doesn't found a new city along those lines. There's a lot of very cheap land all around this vast country, and economic value creation isn't tied to geography as much as it used to be.

Heck, you don't even have to start one from scratch. I live in a midsize city away from the expensive coastal areas with a downtown that's full of potential. It wouldn't take a whole lot of money to truly revitalize it.

There is Poundbury: https://en.wikipedia.org/wiki/Poundbury

Planned cities always seem to get obsessed with far more "green space" than is needed, huge, useless plazas, and very-wide streets, which create miserable, too-spread-out spaces that never stop feeling sterile and wrong. There may be some exceptions, but that's the usual outcome.

Sounds like the California Forever project? https://californiaforever.com/

Most land is already zoned by local authorities, and their rezoning would also be controlled by said local authorities. This type of development is not legal in most of America’s zoned land.

Yep, and thankfully most downtown areas like the ones described by the person you are replying to are zoned for density and new development, and locally elected officials are very incentivized to increase their tax base and do good things for their local economy and so they're willing to work with developers on zoning updates, variances, and approvals.

There are no significant barriers for anyone who is motivated to build.

Problem in most housing constrained cities is 'downtown' is very small. As an example, only about 7% of residential Seattle land is zoned for multifamily, and that is an even smaller portion of the metropolitan area. That's not sufficient for a city that has grown by a third since 2000; and Seattle is considered a friendly city for such multifamily developments.

I agree that what is zoned for a city like Seattle isn't going to be representative of most American cities, and in particular the ones that the person I was replying to was talking about (mid-sized American cities away from the coasts).

Personally I'm less interested in Seattle, New York City, San Francisco, Washington DC, Chicago, etc. because the constraints there don't apply to Columbus, Pittsburgh, Grand Rapids, Oklahoma City, etc.

If you'd like to see for yourself, take a look at a satellite map of a city like Columbus and look at the downtown area. You'll find lots of vacant buildings (well you'd have to just know that so that doesn't really count), and surface parking lots that aren't used that often. If you compare that to Seattle you'll see a big difference.

I find it very confusing as well. Then again it's also typically the same people who say if only you'd tax me more that would fix society's problems and then when you send them the link [1] so they can voluntarily do what they say they want to do they say no! not like that!.

A number of people complain about "billionaires" for being rich and whatnot. My biggest gripe with them is they're often unimaginative and have no taste.

[1] https://fiscal.treasury.gov/public/gifts-to-government.html