300 sq ft of land and a used RV to park on it might be affordable. People might not like some the implications but it's probably cheaper and more sanitary than the alternative of those people in tents.
Counterintuitively, no. People by and large are buying a token for a build site. Look at any zoning area for SFH and a massive portion buy the least acreage they have to.
By creating far more tokens the price spirals down, even though utility rises. The utility of land actually has a pretty weak link to its price.
Take at the extreme of housing fitting into a pinpoint. No one even needs to buy your land even though it now has infinite housing utility -- even though essential it is abundant so it becomes cheap like water.