I still hear some whooshing.
I am not sure I get why you see this as a bad or thing, or at least a thing to complain about.
Sure, the planet is overpopulated and we need to get the birth rate down, make the idea of having lots of children less popular and all that....
But this is about making use of the resources we have already; namely empty homes. Just leaving them idle and unused (filling homes with people - isn't that what homes are for?) won't do a thing about lowering the population. And building more homes while so many are left empty will waste resources and lead to more greenbelt being eaten up.
And yes, screw the owners of these unused proporties. Its not like they won't have a shortage of takers* if they; a.) let the property or; b.) sold it. But if you are leaving a house empty you holding onto something that a lot of people do need and creating scarcity which is driving up high house prices even further.
*Barring homes on sink estates. Even then sell it and at least let housing authority make use of it.