Right but I was talking about the last ~10 years, not 72 to 32 years ago. Berlin (where I now live) also lost a lot of population from the 40s till 1990 but has

Right but I was talking about the last ~10 years, not 72 to 32 years ago. Berlin (where I now live) also lost a lot of population from the 40s till 1990 but has seen a lot of growth in the past decade, thus the current competitive housing market. People also used to occupy far fewer square meters/feet of housing per person in the past so even though Berlin (or Pittsburgh) had a higher population in 1940 than today it doesn't necessarily mean there's a surplus of housing.