Not a chemist myself but Gold has lots of industrial applications because it doesn't react to many other atoms or molecules. For example, it doesn't rust at all. Similar thing goes for platinum. Maybe we should buy the latter..

Gold has always been valued because it has some important attributes that few, if any, other substances have.

It won't tarnish or oxidize, so it will look just as shiny and beautiful a thousand years from now.

It is extremely malleable, easily crafted into any shape. It can be hammered thin enough to be a foil, or drawn into a wire as thin as a human hair.

It has a relatively low melting point, making it easy to cast.

It is extremely conductive, and is the conductive material of choice when price is no object.

There are other unique properties, but the point is that much of Gold's value derives from being significantly, even uniquely, different from most other substances, giving it an intrinsic value beyond its monetary value.

The very article linked to this post talks about civilizational collapse of the US similar to the Roman republic.

Turchin doesn’t track gold but he does track political and societal instability. He believes America has entered what he calls a “revolutionary situation,” where long-running systemic stress can no longer be contained. “It’s not a prophecy,” he said. “It’s modeling feedback loops that repeat with alarming regularity.”

Gold as a unit of currency is only about 2500 years old. Prior to that it was used heavily in jewelry and adornments. Probably because it's not good for much else and it happens to be fantastic as a jewelry material. It's shiney, doesn't tarnish, and is easy to work with hand tools.

The association with wealth probably came about as a result of being associated with expensive jewelry.

To be clear, modern historians do not look for piles of gold to determine relatively how wealthy a society was. They look at their ability to produce grain and other things that facilitated trade. Because gold is only valuable as a mechanism to facilitate trade. To a civilization more worried about feeding itself than foreign luxuries, it's quite worthless.