The US ended gold convertibility in 1971, not 1973.[a] The precipitating factor was actually OPEC's oil embargo from 1973 to 1974.[b] At the time, conventional economic wisdom was that there was a trade-off between employment and inflation, according to the Phillips Curve.[c] So, as higher inflation (and inflation expectations) started getting more and more
embedded into the economy (e.g., stipulated in rent contracts), everyone could see what was happening, but everyone sort of kept waiting and hoping for things eventually to "go back to normal," so no one did anything... until Volcker came along and fought the establishment, causing a lot of pain, to get inflation under control.
[a] https://www.stlouisfed.org/open-vault/2017/november/why-us-n... -- also, see tastyfreeze's comment: https://news.ycombinator.com/item?id=27833523
[b] https://www.federalreservehistory.org/essays/oil-shock-of-19...
[c] https://www.stlouisfed.org/open-vault/2020/january/what-is-p...