A big reason for the current rise in real estate prices is urbanisation (centralisation of population in big urban centers) - e.g. London, NY, SF, and plenty other cities. (The other reason is foreign investments, but I'd argue the investment comes after the initial rise in prices, simply because real estate is perceived as a good investment opportunity.) This urbanisation is to a large extent driven by the fact that the most high-paying jobs are available in these cities, which consequently also increases the availability of lower-paying jobs. I.e. people move to cities to succeed/earn money.
If you remove the last implication - if people can earn a living without moving to big, overpopulated cities - then arguably the concentration of population would drop and the "bubble" would pop/deflate.