Huh? I have a 650sqft house, it costs 430K in a small town. I looked at building a new place, it would cost roughly the same to hire a building team to make it - not to mention years of waiting on development. The land is fairly affordable if I buy a little bit out of town. It's the cost of building that is stopping me.
If I look at the value of the place where I'm living, a bit more than 2/3rds of it is attributable to land instead of structure. This ratio will change depending on whether you have a multistory structure on a small plot of land, or a SFH with a yard on a larger plot, but land/value ratios > 50% are typical.
I had a 1200 sqft house built for about €180,000 in Ireland.
If it's costing $650+ per sqft to build, it sounds like there may be some externalities about the site(s) that might be relevant here?
For scale, in much of the country it is possible to build a new home for well under $200/sf. New detached homes retail for <$175/sf, which includes the builder's profit.