No game theory account for such scenarios too. The ones not playing by the rules are normally psychopaths and the like, so game theory is about handling that type of scenario when the normal rules no longer apply. It’s not just about simple greed, people brake the rules for various reasons. Psychopaths like Trump and the White House, simply feel more entitled, and they need to be shown very clearly that it will not be accepted.
We absolutely need to respond to Trump according to game theory, because you can’t control him by throwing him a cookie from time to time, he will always come back for more until he is stopped. The exact same as with Putin, despite they are different psychologies.