USD and other IMF SDR basket currencies maintain their exchange rates despite excessive supply because there is an excess demand to match.
USD and JPY maintain their excess demand by lending out newly created currency for interest, but only the principal is created initially. And the interest is almost always never created.
The principal is used by the borrower nation to pay for infrastructure and weapons bought from the corporations of the lender nation. These corporations then park these dollars in a way that does not raise prices of common goods. They use means like bonds, and equity in other corporations and in startups to do it (this is how Snapchat fetches billions of dollars in capital).
The interest needed to pay back the original loan creates a perpetual excess demand for the lender’s currency.
The lender uses such an excess demand for their currency, combined with excess supply and the resulting cheap capital of lender’s currency to fund innovation and technology superiority in its local community.
The problem, however, happens when easy money leads to more corruption, more propaganda, unwise movements to make the world more socially-just/progressive/protestant/Catholic, and the eventual drying up of innovative ideas to tap into and create a technological dominance out of.
Once that happens in order to maintain foreign excessive demand for the lender’s currency, the lender nations will have to start selling weapons and even create wars to spend the weapons on.
The world will then go to war with each other, while the local communities of the lender nations will stop breeding thanks to divisive propaganda and unwise ideological indoctrination against sexes, races, and religions.
Corruption will do the rest, by gradually eroding trust in the State to fix problems, and create private alternatives like the Mafia instead. Private gun ownership might help stave off total destruction.
Second law prevails as usual. Without external systems to export entropy to it creates entropy within. In this case, the system is the world.