A few years ago, Janet Yellen (testifying in congress I believe) called for more research into "hot" economies because presumably there was a lack of such research. We're now in a period of growth and basically full employment after a pandemic where the fed and fiscal policy decided to keep things "hot." There have also been supply and energy shocks that are contributing to inflation.

The remaining part of the MMT puzzle as I see it is: raise corporate taxes, and see if it helps bring inflation under control. If raising rates slowly doesn't quite do it, this should be the next go to for policy makers.