Also, one thing that I have never seen being talked about that has increased the demand for housing many fold in the last 50-100 years is the fashion of people leaving their family homes in their twenties. In traditional societies, it was common for at least one child to continue living with their parents for their entire life. It was thus very common for every household to include three families - a pair of grandparents, one of their children with their spouse, and one of their children with their spouse.
Instead, today, people tend to live with their parents only until around 20-30. Getting married while living with your parents is virtually unthinkable. This means that the supply of houses has to be at least three times greater than in a traditional society, with a higher percentage of temporarily occupied housing as well (since even though you can eventually reuse your parents' and grandparents' home, you need to live somewhere while they are still alive.
Of course, there are tradeoffs, and I would be extremely hypocritical to claim that I'd like to live with my parents and grandparents as an adult. But, such preferences are formed by fashion and social expectations. The millenia of this being the norm at the very least show that it is workable.