This comment highlights the most crucial insight on QE: it is a relatively novel monetary policy innovation that was implemented as an emergency response to the 2008 crisis on a very large scale and, as such, we had no experience using it. 14 years later, we’re finding out what it means for an economy to have the Federal Reserve buy a large amount of US debt.

QE isn't novel by any stretch, even in 2008. The Federal Reserve had a similar program back in 1930s around the Great Depression and the Bank of Japan has had a full-swing QE program since like 2001.

It wasn't that long ago the USA confiscated gold from its citizens via President Roosevelt's Executive Order 6102 in 1933.

I don't think we are finding out that much. Most other countries are experiencing the same inflation we are and not all of them deficit spent a lot during the pandemic. Nor do most even have that power.

Surely some of the inflation and really low unemployment is due to QE. But it's likely a lot more of it is due to an economy growing while the active workforce is shrinking and external factors like the pandemic and war in Ukraine causing supply issues.

Notably, it's a temporary creation. As those bonds get paid off, along with interest, the fed must either roll that money over to buy more, or simply disappear it off their balance sheet. Which is part of what they are doing now with Quantitative Tightening or QT.