In the Mythos blogpost they revealed to run the model like a 1000 times on the same code-base maybe with slightly different prompt or temperature. That suggests it will just be pay to win. If the 'attacker' spends more money/tokens than the 'defender' you will eventually be outclassed.
The problem is that it is making Spotify money if they substitute real artists by generated music that they produced themselves. They will have to pay a smaller share of their money to actual artists.