The thing is that "inflating it away" isn't a serious long-term proposal. Suppose we were do something drastic, like target 6% intentional inflation, obviously nobody would buy bonds at 6% anymore, they'd demand at minimum 12% (because they'd lose 6% of it due to inflation). Once they demanded 12% the interest payments [on the gov debt] would shoot up well above 1t, and then the amount we'd need to inflate would again spiral up. The spiral runs away, there's no secret cheat to a free lunch.