The desert island scenario, however, is also a good metaphor for a state of society that we could find ourselves in should things really get bad. You can’t eat gold. You can’t keep yourself warm with gold. You can’t wear gold. That is the point. It all depends on how bad things get, and how long the badness goes on.
I think its clear that while those things will help your family survive a crisis, gold will help your remaining wealth survive the crisis.
When it comes to the “you can’t eat gold” cliche, tell us what investment or store of wealth you can eat, and why that should be a goal?