The number is irrelevant - people want to live in desirable areas where's there are jobs, and are constrained as such. Rebuilding high density in towns and cities is an issue, as well as maintaining decent services ( hospitals, roads, public transport, post office etc).
You say that houses are being treated as investments, that's why these crises happen; but then why are building materials and tradespeople also at sky-high prices (in Ireland)? Is it all competition on investment building?
