Indeed. For some reason this obvious conclusion doesn't satisfy the pyramid theorists, even though ancient Egypt's many periods of cultural decline and later resurgence are well documented.

the economic case is more compelling in this example. grand central is still largely the same structure that was built in 1910 at the peak of rail's dominance. penn station was demolished and rebuilt to sell air rights during a sharp decline of intercity rail ridership.

I guess demolishing an iconic building could itself be evidence for cultural decline, but stuff like TWA flight center was being built at the same time. the dollars followed the passengers.