You make some errors.
Okay you gold bugs cannot have both ways.
First, I'm not a gold bug. I am currently short silver and have no position in gold.
If GOLD is the only unit of value that is REAL?
Then the " returns" one makes buying and then selling gold are illusionary.
Why?
Because the gold really didn't change its value while you owned it, all that changed was the exchange rate with dollars.
So make up your minds.
Either you own gold and it has the value of gold as long as you own it (and everything else is FIAT) or gold is just another commodity with fluxuating values depending on the market for gold.
It cannot be BOTH.
If gold is the unit of measure then gold cannot rise in value.
All value is relative. Value is never static, including the value of currencies. If you view gold as a currency relative to all other fiat currencies, then it will act just like all other currencies.
Currencies facilitate trade in goods and services, which fluctuate in relative value. The price of oil fluctuates up and down relative to the price of a car. But rather than bartering oil for automobiles, which is enormously cumbersome, we use currency. This facilitates trade. Similarly, the price of a German car fluctuates with the price of American oil, and the relative value of the currencies used in the two countries will also fluctuate relative to the supply and demand and thus the terms of trade between the two countries and their goods.
If you are thinking about buying a German made car that is priced at $30,000, and the euro is worth $1.50, if in a year the euro falls to $1.00, then that exact same car costs you $20,000, and you now have $10,000 extra that you would not have had had you bought the car a year before. Similarly, if gold is $300 an ounce and you have 100 ounces of gold, you can buy a German car now for 100 ounces of gold. But if gold rises to $1500 an ounce, you can buy a German car for 20 ounces of gold, and you have greater purchasing power because you have more gold relative to the price of cars.
All currencies are about relative exchange. If your currency appreciates, then so has your purchasing power. That's the point.
If gold is just another commodity then one CAN make or lose money on its price in comparison to FIAT specie.
I KNOW you gold bugs will NOT get the above.
Your concept of what money really is is too clouded for you to understand why gold is just another commodity.
I get the concept of money just fine, thank you.
It is not an "either or" proposition. Gold is both a currency and a commodity.
Using your argument, then the dollar is not a currency either because the price of the dollar relative to all other currencies also goes up and down, depending on the market for dollars. Currencies fluctuate all the time. The fact that the price of gold goes up or down relative to other currencies does not mean it is not a currency. And like any other currency, you can make or lose money trading it.
A currency is whatever people accept as a currency. In prisons, cigarettes and
cans of mackerel are currencies. Cigarettes have been used as currency during hyperinflation. Milton Friedman noted the story of the islanders in the South Pacific who used giant sea shells at the bottom of the ocean as currency, even though no one ever saw a shell.