I don't disagree. I addressed this in my post. I don't claim to have a definitive claim that it has outperformed nor do I believe it has. But its curious that it's even up for debate. A fixed supply of something, basically a unit of account. If you denominate prices of "productive assets" in terms of gold, the return is considerably lower when compared to that of fiat.
Gold appreciation was ~0% from 1930-1970. Post fiat-currency it grew at 5-7%. That has to mean something...