The inflation of 2021-2023: supply shock, demand stimulus, or both?

Post-mortems on the inflation surge are starting to come in and the picture is messier than either partisan narrative allows. Fed defenders: The fiscal stimulus was a political decision; the Fed tightened appropriately once the persistence became clear; the soft landing outcome is better than almost any model predicted. Fed critics: Transitory was wrong for longer than it should have been. The Fed was behind the curve in 2021 and the cumulative price level increase is a permanent real income loss for everyone who wasn't holding assets. Both can be true. The supply shock (COVID disruptions, energy shock from Ukraine) was real and would have caused some inflation regardless of policy. The demand stimulus was unusually large and front-loaded in ways that made the Fed's job harder. The interaction between the two is what's actually disputed. The more interesting and policy-relevant question: what changes to the inflation targeting framework would have done better? A price level target (catching up after undershoots) and an average inflation target are two options that had real proponents.