https://www.cmi-gold-silver.com/article/gold-standard-inflation-fiat-money/ is the source of the quote.
I did some research on the value of the dollar over the course of US history (at least, as far back as I could find. What I discovered was that the value of the dollar relative to the *median* price of gold over the last 225 years has crashed significantly and not recovered twice. *Only* twice. Once was at the beginning of the great depression, and the other was the minute the gold standard was abolished.
Note: There was a scenario on a similar scale of the great depression during the Colorado Gold Rush of 1859, but this only applies to gold and I think this is due to peoples' tastes and preferences leaning towards gold. The gold rush must have affected demand more than supply, because the price nearly doubled. That's the only thing I can think of to explain it.
Regardless, the price of gold returned to the median in just a little under two decades — very short in the history of the US. Here are the excel graphs I made that caused me to discover this phenomenon. https://imgur.com/a/FpEVl0W