“Over the past 25 years, since January 2000, the price of gold has nearly doubled the S&P average. ”
...
You chose your time frame let me choose mine.
Sometime during 1980 both gold and DJIA were $850. Today gold is near $4,000 and DJIA is $48,0000.

Good point, but extend it even longer:

The main case for owning gold is also the main case for NOT holding gold.

The case for holding it is that it has held its purchasing power (within a range) for millennia, so it will probably continue to do so, no matter what happens to the world's financial systems. Fair enough.

But the case against it is that it has merely held its purchasing power (within a range) for millennia. We're in the high half of the current price cycle at the moment, so the gold bars are a pinch shinier than usual, but an ounce of gold doesn't really buy any more "stuff" than it did 100 or 500 or 2000 years ago. So it isn't an investment in the conventional sense. An ounce of gold has a market value sufficient to buy one of the best men's suits available--same as always.

Jim