Actually, that article to me speaks of a dynamic society. As the fortunes of different industries change and the relatively economic success of different regions change, people move elsewhere. In some extreme cases -- which is all they are talking about in this article -- like Detroit or Flint, you end up with such a large empty housing stock that it makes sense for some collective action to demolish some neighborhoods and make room for something else or just increase the local parkland. The sort of cities being talked about are ones like Detroit where something like 1/3 of the houses sit empty today. Really, Detroit is almost alone in that category.

On balance, the US population is still growing nicely. Current crisis aside, for every Flint there are a couple of Austins or Charlottes or Seattles.

I guess I'm not sure of your point -- it'd be a _good_ thing if people sat in Detroit waiting for govt handouts instead of moving somewhere else where there are jobs? Or good if the govt did even more to keep jobs where they are today (or were yesterday)?