I think it probably could be cheap enough. Part of the issue is actually just that new home sizes keep getting bigger. Like yeah, new homes are more expensive now even in relatively cheaper parts of the countries compared to decades ago, but it's also true that the homes are much larger than they used to be.
A lot of the homes from the 50s and 60s that people talk about being very affordable at the time they are made, were very small things by today's standards.
