There is a little problem: land is expensive, frequently land drives the price, not the cost of building a house.
Nevertheless, they could maybe build many of these homes close to each other, several on one lot, to make them less expensive.
Of course, people could just rent an apartment.
There is a little problem: land is expensive, frequently land drives the price, not the cost of building a house.
Land, zoning requirements, and building codes. Physically, houses are not expensive.
It is all the legal requirements and the cost of the land that make them expensive.
This technique reduces the physical cost a little, but why would you put a $4,000 house on a $40,000 lot?