It was deliberate, on one of the financial summits over the future of financial system after WWII a US changed all the word of GOLD to USD.
there was a planet money episode about it.
https://en.wikipedia.org/wiki/Bretton_Woods_system
This has a link to the PMoney episode you're thinking of, as well as a more recent discussion of the economic fight other nations possibly trying to supplant or at least be adjacent to the dollar as a reserve currency.
https://www.npr.org/sections/money/2019/07/30/746337868/75-y...