Your point stands though. If these things are crashing then surely they would have crashed on some Third World hell-hole where the population would happily collect the debris and sell it to whoever wants to pay. It would be hard to cover something like that up. The US likes to think they are everything, everywhere, all at once, but it's not entirely true.

For entertainment, consider that the Cold War could have been about finding intact UAPs, at least in some of the scuffles.