An ounce of gold is traditionally viewed as a months wages. And it hasn't changed much but there are some fluctuations.
Interest rates and inflation are artificial constructs that are fiddled with to screw you out of your money.
A lot of other tangible assets were dramatically cheaper in 1969.
Using the gold example- suppose industrial demand for gold to fuel the semiconductor industry tripled the price of gold compared to 1969. Now suppose the price of milk, bread, gasoline, electricity, water, clothing, and alcohol only doubled in price compared to 1969. If inflation is a measure of your purchasing power IN GENERAL (not your purchasing power of gold), inflation was roughly 200%, no?
If gold had absolutely no practical value by itself, it would be free of market demands like that in my example. But of course then its value would have no connection to purchasing power, and we're right back where we started.