I think #3 is compelling -- the neverending total war and global conflict is entirely a function unlocked by fiat, which is certainly something a progressive can get behind.

The thing that I'm not sure about, though, is the game theory of it -- you could have a country that stuck with a commodity money, and keep the assorted benefits of sound money, but if their "competitors" had access to this warmaking capability unlocked by the money printer, the gold standard peeps get weeded out of the evolutionary pool. On the short term, the ability to coordinate human action at scale in service of some small cadre of people is a massive advantage -- that's why it happened in the first place.

So I'm not sure what to think about this argument from a pragmatic perspective, even though it's true.