Gold and silver have very little inherent value, only trade value (other than a few industrial applications, but they can often be replaced by copper). We don't save very much food, or surplus housing, or surplus machinery or petroleum or solar panels, mostly because these things degrade physically and become obsolete when saved. Instead, we rely on today's economy to provide these things.

Total worldwide gold production amounts to $132 billion, or only 0.2% of world GDP. Even if we saved all the gold mined every year, it wouldn't support any substantial amount of real saving.