Can't deny it is a factor. Not a single mention in the article though, of course. It's all discussion of the resulting effects, and the supply side.

Demand side has multiple parts:

- National population growth (migration, as fertility rate below replacement)

- Money supply inflation (government spending, mortgage borrowing, years of artificially low interest rates) allowing people to bid up prices

- Urbanization (office jobs and universities); people within the country move to the big cities

- Social atomization (more housing needed per person)

(EDIT: Ageing population too: children tend not to have their own place)