Yup. And if they print so much money that it becomes worthless, then that'll have a similar impact on lenders than if they just default, which is the governmen

Yup. And if they print so much money that it becomes worthless, then that'll have a similar impact on lenders than if they just default, which is the government's first option and everyone else's only option. The government's only option, too, if the debt is denominated in someone else's currency. To that extent, governments having the option to print money to satisfy debts is a good thing. As soon as there are two evils to choose from, it becomes possible to select the lesser of them. In other words, don't think of lending money to a government in a currency it can't debase as if it were somehow less risky. There's still plenty of risk, it's just that it comes entirely in the form of default risk rather than as a mix of default risk and exchange rate risk.