1. The government requires banks buy their debt and hold it as reserves because it's considered the safest investment. 2. The government decides that, oops, it printed too much money in 2020/21 and is causing inflation, so it raises rates very quickly. 3. New treasuries yield 4 or 5 times as much in interest as the ones from 1-2 years ago. Why would anyone want to buy those old treasuries near face value now? 4. The…
What caused this wave of inflation was supply taking a hit. Fallout from COVID and then war in Ukraine. It was difficult to get many good which normally were easily available. It's not rocket science either: inflation is about always caused by falling demand. It doesn't matter how much the government prints. When bread is hard to get people will exchange a lot to get a loaf.
If anything it seems like overreaction by the feds to raise the rates so much. It's not like them reducing access to capital magically makes goods appear on the shelves.