I wrote 2 paragraphs but I erased them, I'm sure you understood what my exact point was, but since your comment is not constructive at all, making stupid assumptions, comparing possible Kardashev civilizations with history, I will just post a link[1]. If you care follow it, if not, I don't have anything more to add.
Like, you do realize that no one in the history of mankind has a use for something which "stores value" for millennia right?
And that timescale is so ridiculously huge that gold, silver and everything else does inflate away. We might be a type II Kardashev civilization in 1000 years. The volume of gold available will be absurdly large by then either way.