Your post - All conjecture. You do realize that, no?
But actually looking back at some posts from about ten years ago at a couple of my forums there were one or two people who were adamant about staying away from stocks bonds and cash and predicting the collapse of all currencies within five years and that only tangible bullion like gold would be worth holding.
Hasn’t happened yet.
The US left the gold standard in 1971, and paper money started in western civilization in the 17th century. I don’t see us reverting to bullion only, sorry. Not ever. Even if we had nuclear war and most everyone and everything were wiped out why would gold then become valuable?
If indeed everything collapsed I think we'd revert to a barter system, not necessarily gold. What good would a hunk of metal be if everything around centralized government including banks etc. were gone?
I recall this classic Twilight Zone episode where robbers stole a bunch of gold and then placed themselves in suspended animation for many years to escape the consequences. When they returned, they started killing each other over the gold not aware that gold had become worthless in future society when science figured out how to manufacture it artificially.