Even with the rise of tiny houses (with a new push by HGTV), most American new homes are nowhere near this small. According to Census data, only 8% of new homes constructed in 2014 were under 1,400 square feet. And the median square footage for new homes was 2,453 and the average was 2,657.
As noted in earlier posts, the size of the tiny house movement is unclear. They may be popular in particular situations such as cities with affordability issues (like San Francisco or New York City) or dealing with homelessness. This is the case even with a sluggish housing market for starter homes and the burst housing bubble of the late 2000s.
What is the future for tiny houses? I suspect it will continue as a niche movement. Many Americans still like larger homes and their stuff and have a hard time imagining paring down their life that much. Perhaps semi-tiny houses will become popular: the 100-200 square foot homes ask for a big sacrifice but housing units of 700-1,000 square feet are doable (and not already uncommon in denser cities). It might take the efforts of a major city or developer really getting behind smaller homes to convince a larger group of people that this is the way to go. But, outside of specialized uses, it would take a big shift to get many to build and/or buy such small houses.