I think the only way for the universities to escape this blackmail trap is to bind together in their response, refuting the Trump's claims that they're not doing enough to "stop antisemitism" (obviously a cover chosen by the WH because it immediately gathers public sympathy), and reject Trump's demands. If they cave in now, it will be used against them again.

Take the haircut and wait for either the next presidential elections, or maybe midterms if the GOP gets pummeled because of this and starts standing up to Trump. One thing we've seen about Trump is that he fairly easily reverses course when the right pressure is applied.

Granted Harvard's in an easier place than most, but I predict Columbia will come to seriously regret their decision.