So the US government ould rather profit from money laundering than take the bills out of circulation.
Which says rather a lot, I think.
That the American government is rational. For there’s only that seignorage profit if the $100 bills are used outside the US and don’t return. Meaning that the profit comes from people dodging taxes in Russia and the like. And it really is Russia etc. I recall well when the $100 bill changed. A friend ran the bank note importing company into Russia – all legal – and the US Treasury was sending billion upon billion of the new notes into the Russian system.
The US government profits from foreigners skimming their own governments. Given that the US government is supposed at least to be working for Americans this seems like an excellent deal.