Historically, wealth and technology cause people to consume more square footage even as household size is reduced.

I am concerned that this same trend will play out and also that wealth concentration and lower rates of population growth (or decline) will lead to much less new construction and that where there is new construction will either be in a boomtown setting or relegated to wealthy people building large homes.

The rest of us will probably just have to make use of and manage the decline of the existing housing stock as it is and where it is.

The average age of housing in the United States will likely always be in the 20th century.