The depeging occurred in 1971:
* https://en.wikipedia.org/wiki/Nixon_shock
the CPI didn't start going crazy until the mid- to late-1970s:
* https://en.wikipedia.org/wiki/1973_oil_crisis
* https://en.wikipedia.org/wiki/1979_oil_crisis
* https://en.wikipedia.org/wiki/Supply_shock
though there was a rising amount before any of those events:
* https://www.federalreservehistory.org/essays/great-inflation
You'll find that real wages in the US were fairly steady for most of the 1970s, falling mostly at the end, and really dropping during the 1980s:
* https://www.factcheck.org/2019/06/are-wages-rising-or-flat/
kinda like how despite all of the inflation the average person only saw a 3% increase in actual take homes while the hyperwealthy saw 300% (of much, much larger numbers).
it ain't gold, it's greed