Gold is valuable because there's a perception of gold's value. It works as a currency. Like Salt, or tea bricks, or gems, they have some applications, but were being used as trade goods because of the perceived value.
My point is simply that people in the 1400's didn't know that petroleum would become as important as it is or that high purity sand reserves were magnitudes more valuable than "regular" sand or that pounds of sugar would only cost a fraction of a laborer's hourly wage.
If the worry is "inflation/devaluation of a currency without without the complete collapse of modern society" SOMEBODY will have a valuable currency. You could just as easily say that instead of storing gold you could store bank notes from several different nations. You could also store bitcoins, or bricks of drugs, or all sorts of things that carry value in the current climate. Hoarding wealth in the form of non-useful items is a gamble. You're assuming someone will want your currency. It's plausible they won't. Wealth, as opposed to trade goods, is only worth how much someone else wants it.