No fiat currency would fare any better than the USD. Fiat currency is socialist currency, because it politicizes/socializes control over the supply of money. The power elite know this quite well. So any proposal for a new world fiat currency is all about international power politics (who will control the supply of the principal reserve currency,) and not at all about fixing the fundamental problem (which is that the supply of money must not be politicized/socialized.)
Let’s see the U.S. currently pays for about 25% of the UN’s bubget. Since our currency is worthless in their eyes, we should stop immediately giving them any financial support. Next, since they insist on trying to override our Constitution, they should be expelled ansd we should withdraw. People who want to deal with us will, those that don’t won’t. We’re still 25% or so of the world’s GDP. That matters more than a bunch of oneworld assholes trying to undermine this nation in NYC.