It's a good question and I don't really know the answer but I think that the creation of the Fed was a major step forward in the adoption of fiat currency which (in my opinion) is fundamentally flawed because it essentially weaponizes inflation. There were positive benefits to fiat currency in winning the WW's and redistributing wealth during the New Deal but more often it is used to fund agressive warmongoring or (as it evolved) to transfer wealth from wage earners to asset holders.
Related: Found this interesting chart of the dollar's value going back to the 17th century.
https://www.statista.com/statistics/1032048/value-us-dollar-since-1640/