This might actually be more in demand today than when Mr. Fuller originally invented it.
Part of the problem is that like clothes, houses and exterior/interior design follow fashion trends which have nothing to do with utility and maintenance. And like the tax prep industry, there is incentive for builders/contractors to make houses fragile and hard to maintain so they always have (expensive) work to do.
The HN thing to do at this point is to believe that I, a software engineer, can do better and then fail spectacularly in doing so because building houses is different than writing code. So instead I will sit here, fume about the state of things, and throw money at problems when they arise.
The thing is, you probably can do better, you just can't do it both better and as fast or faster.
It's totally worth doing it better for your self to utilize and enjoy. The calculus is entirely different vs. a business effort needing to turn a profit. Most people have plenty of hours they'd otherwise spend unpaid wasting time they could instead be investing in improving their homes while learning new skills.
Drywall, mud and paint seems like a lot of work, but imagine making a room 30 feet long where replaceable panels actually looked good and fit well.
We're also some 4.5× more people if I remember historic figures correctly, and presumably the number of households increased even more. Particularly with urbanization as well as lower transportation costs, might be a lot easier to find buyers even if the per-capita demand were to be equal or lower.
I'm intrigued enough to want to try one out if I can reasonably get to it (perhaps as part of a bigger trip), though as someone who doesn't plan to own a home in the next decade or more (I'm 30) I'm not really in the market.
This would otherwise be expensive and wasteful of water and energy, but it doesn't take much of either to keep the shower flooded with steam. Plus I'm not drying out my skin while trying to stay warm with too-hot water; cool water in the hot environment feels great for wash 'n rinse. It also feels good to breathe the steam.