> You can build useful things with it.

A vanishingly small percent of gold's value is attributable to its industrial use. Of all the gold ever mined in history, only something like 1% has been used in an industrial or construction context.

Maybe if you extend "useful things" to jewelry you might have a point. But almost assuredly jewelry is made out of gold because gold is expensive and valuable. Not the other way around.

If everyone on Earth tomorrow forgot about gold's historical role as a store of value, it might be worth $50 an ounce at most.