Two things are occurring in parallel that make absolutely no sense.
Virgin land is continually being developed farther and farther away from the city's core. Massive amounts of money must be spent to build roads, install water and sewer lines, provide garbage collection, provide police and fire protection, parks, schools etc. to these areas. For the most part, these areas do not generate the tax revenues nor the impact fees to cover the cost of these services. The difference is covered by those living in already developed areas.
Meanwhile tax revenues are being used to tear down existing homes that already have utilities, paved streets, and already served by public safety. Yet there are no plans and likely won't be to build something new on these sites. As fewer and fewer people are served in these previously developed areas, the cost per resident to continue to serve them goes up.
How long can that last before it simply can't be sustained?