Except that's not how it happens. Demographics have been collapsing in many EU countries for a while now and prices have been going nowhere but up at rates beyond wage growth.
Internal migration from rural to urban, and external migration from war torn and impoverished nations also to urban centers, keep pushing demand up regardless of local reproduction numbers.
Sure, you can now buy cheap properties in some empty towns in the south of Italy for example, but to what end if there's no jobs there?