A supply shock has hit. The recession is driven by the supply shock. If there is less stuff to have, fewer people will have it, which means there will be less business activity. That problem cannot be solved by printing money. It can only be "solved" by rationing. The question is, rationing by what test?

One way to ration is by pricing. That's what inflation does. Those with less bargaining power vis a vis the sources of their income get less stuff. Another way is to ration by creditworthiness, which also affects those less able to earn more money. But raising interest rates raises nominal costs less and is, at least arguably, less disruptive and distortive than raising nominal prices alone. I won't make that argument here. I'm just saying that the Fed is no more powerful than King Canute. It cannot prevent a supply shock from causing a recession. It can, however, to some extent substitute higher costs of credit for higher nominal prices. That's a job worth doing.

Printing money won't fix a supply shock. It will fix a demand shock. And it may prime the pump after a supply shock has reduced people's ability to demand once the supply constraint has eased. I mean, I like MMT as much as the next guy. But it can only do what it can do.