The asset is used to back up the counties own currency, a protection. All money is worthless, a piece of paper, a figure on a screen. If that country finances collapse as the mark did post war, the gold held as assets allows the country to continue trading. Its something to be sold during...
Selling the gold you don't need hindsight to know not to flood what was a depressed market driving the price to such a low. You need a brain. He sold a tangible asset, a massive lump of physical rare material not a business so it is plain stupid to compare.