The barrier is, the construction industry's "awful" productivity.

It cites this paper:

https://bfi.uchicago.edu/insight/research-summary/the-strang...

the number of houses or total square footage (houses are getting bigger) built per employee each year was flat or even falling over the last 50 years. And the researchers believe the lack of productivity growth holds true for all different types of construction.

And:

According to an estimation by the McKinsey Global Institute, construction, one of the largest parts of the global economy, is the least digitized major sector worldwide—and it isn’t even close.

I always get a kick out of articles like this. We know precisely why there is a housing shortage and why fewer and fewer houses are being built. Even knowing why won't change the situation.

Easy to see why aren't they improving. There are legal limits to the amount of housing that can be built, because of zoning and NIMBY. So if they became more efficient, they won't build more - they'd just fire some of their workers. Now unions prevent that because construction industry is heavily unionised.

Fix? There is no fix until less than 50% of voters will be satisfied with their housing situation. Then, pro-housing candidates will get an upper hand.

My belief is that in free society, in long term, housing has to be a limiting factor - democracy itself dictates that, because people want their homes to build equity and these people vote.