>...where the analogous thing would be to create more "nice places to live" with all the desirable attributes like walkability, jobs, public transport, etc. It's a tall order since land and climate are the ultimate scarce resources, but there are probably some underutilized spots that could support it.
Absolutely. And in fact there are lots of places that could support such things. In the US we call them "small towns" and "rural areas" and "the rust belt."
Areas where a lack of good jobs (as manufacturing left and farming became much less human intensive) drove folks to where decent jobs are (were?) more available.
Which drove up the costs of housing and, well, pretty much everything else, in those places.
However, with the technological changes we've seen over the past eighty years or so (Interstate highways, compute/semiconductor industries, ubiquitous networking, etc., etc., etc.), revitalizing those areas that have been left behind could boost both local economies as well as broader ones.
However, ALEC[0] and its corporate backers have sabotaged efforts to do so in pursuit of destroying competition and maximizing rent seeking. a lack of infrastructure maintenance is part and parcel of that -- as a lack of economic activity reduces the amount of tax revenue available for necessary infrastructure repairs and investments.
If companies could get symmetric, multi-gb internet, decent office space with decent road and rail connectivity to/from regional hubs in small towns and rural areas, more people would move in, prompting more housing development, more local businesses, more tax revenue, better infrastructure, etc., etc., etc.
This type of investment could have instant positive economic effects in poorer areas, and longer term (coupled with more housing), reduce the insane housing prices you see in NYC (median apartment rent in Manhattan is ~$4500[1]), SF, Boston, etc.
Unfortunately, statehouses appear to be fully captured by big corporations wanting to maintain their rents by stamping out any competition, the economies of those states be damned.
Sadly, the above can't happen unless the folks in those areas stop voting (in municipal/state elections) for the folks who are supporting policies designed to maintain the penury endured in those places.
There are so many good reasons to reinvigorate these areas, but we keep electing folks that won't bite the hand that holds their leash.
[0] https://alec.org/
[1] https://www.brickunderground.com/rent/nyc-manhattan-brooklyn...
Edit: Added the missing links.