Many places treat these types of dwellings as mobile homes, and there is probably no form of development that is more widely banned than mobile home parks.
Even putting one of these on your own lot as an accessory structure is going to be very difficult in much of the country.
These rules are all legally codified class discrimination, and is very much largely about middle class single family homeowners keeping out what they call "undesirables".
In their worldview, "undesirables" can include anything from a mixed use building with commercial on first floor and an apartment on top, to turning a single family home into a duplex, but there is nothing more detested by these folks than mobile home parks.
It's an American caste system and it leads to unnecessary high housing prices. Very broadly, America doesn't want to invest in fixing social problems and there is a big focus on just moving the problem to other areas. The counter-productive part of this is that high housing costs drain resources from families and that induced poverty state leads to the social problems that are trying to be hidden in the first place.
Zoning is in need of serious reform, it is possible to go up against it and it is possible to win. I have, but it wasn't easy, and you really need public opinion on your side.
Market positioning can make the difference, and there is opportunity for things to change due to the bad economic position many towns find themselves in. Many places simply can't afford their snobbery anymore.
The rebranding happening with the tiny home movement has a chance at breaking through this and I hope that it does.
I would love to develop a piece of land with a group of affordable small houses but it's a total non starter in my area.
