This appears to differ across Europe.

I know for a fact (through living here) that Denmark and probably the rest of Scandinavia has property tax and inheritance tax -- holding on to family property is almost as expensive as buying new property.

Which part of Europe are you referring to? I once had Greek colleague who complained about having to maintain three generations worth of houses, so that might be one place where things are as you describe?

I think you can argue migration (forced) through history is tied to this. The US was a recent star in growth due to free land. But there is no more free land. And Mars does not fill that role. We need to disempower rentiers.