Gold is a really useful material

It’s not that it would need to be as valuable forever but rather the opposite: that it be forever not looted.

Indeed, it is a reasonable assumption that it will get more valuable over time, as it is a scarce resource.

Gold is extremely common in the solar system.

In the next few hundred years it's pretty likely that gold price will be marginal, as asteroid miners looking for less useless materials such as nickel, cobalt and platinum mine an excess.

So no, unless for some hidden reason asteroid mining doesn't work out, which is pretty unlikely given how badly the developed world needs that material.

But wouldn't use such miners make the extraction cost higher?

Gold is quite useful as a corrosion-resistant conductor. If it wasn’t, cheaper metals would be used in its place in electronics.

This thread reminds me of a Twilight Zone episode.

https://en.wikipedia.org/wiki/The_Rip_Van_Winkle_Caper