Some inflation might be good, in particular if it allows for higher real wages, something sorely needed. How much inflation? Difficult to say, but the structure of the Fed is not going to vanish, and higher rates would be used to discipline the labor class, with the support of many neoliberal Dems … The limits to fiscal expansion would be political, not economic, and there is no reason for the left to be up in arms against an imaginary enemy. Hyperinflation is like the the windmills for the Quijote. The giants to attack are actually the ones pointed out in the progressive agenda, like lack of spending on health, education and the environment, and MMTers have been instrumental in getting these ideas in the political discourse, and moving the Dems to the left.