Ask them about the Concorde: 15 years ago you could fly across the Atlantic at Mach 2; now you can't. Why? Easy: technology that doesn't pay for itself eventually shuts down when the financing goes away.
Apollo was exactly the same. No bucks, no Buck Rogers.
Two Thousand years ago the steam engine was invented.
The first commercial steam engine went to work in 1712
Perfect line, perfect delivery !