Author of this paper says it shows there is no “quick fix” for housing problems but it seems to clearly support the view that if you upzone in affluent areas that will work. https://twitter.com/tony_damiano/status/1317160871605510144

The point of zoning reform isn’t that the dynamic of new building on the gentrification frontier is good, it’s that it’s *bad* and regulation should allow new building where land prices are highest (i.e. where rich people live).

Talking about “submarkets” doesn’t really complicate this analysis — that’s the whole point!

Of course even if you improve housing policy you’re still left with the fact that poor people need more money — so give them money. https://www.vox.com/2019/5/17/18628267/jenny-schuetz-weeds-interview

I would note that the submarkets empirical literature in a broader context seems ambiguous.

Evan Mast finds that new construction reduces prices in all submarkets. https://research.upjohn.org/up_workingpapers/307/

Davidov, Pavlov, and Somerville find that when you add laneway houses to a rich neighborhood in Vancouver prices go down while the stay flat in a lower income one.

https://open.library.ubc.ca/cIRcle/collections/facultyresearchandpublications/52383/items/1.0376805

So there seems like an unchallenged finding that market rate building in expensive neighborhoods reduces house prices and some divergence across cities (or methods or circumstances or something) in the poorer ones.

A good research subject but a simple policy prescription.