There's both plenty of gentrification and plenty of walkable, human scale development here (Germany), so I don't buy that that's the cause (although it might exacerbate the problem).
I was referring to the US, pardon that. In Germany it seems even recent cities can have buildings spaced close to one another and without forcing people to pay for parking.
This is untrue in most of the US; case in point, a person who wants to turn an old building in to a restaurant in LA, even near transit, has been forced to add 21 parking spots. To do this, they are tearing down the house next door, exacerbating an already difficult housing shortage.
For Germany, my understanding is that it's still not too horridly expensive - is that correct? Last I heard Leipzig was the hot new place, and it doesn't seem fiendishly expensive (note: I've been desensitized to some extent by living in Berkeley and Santa Monica)
Leipzig, like several other eastern cities, is the "hot new place" because it's still relatively affordable. The American equivalent might be Pittsburgh.
In Munich, Hamburg, Frankfurt, etc prices are much higher.
