There are still many other places they can advertise – just not so easily in the US.
And, to be dead honest, they might not even be too worried about a reduction of exposure in the US market. I assure you, if they were worried about the US market, they definitely would not have dared to take this type of ridiculous action.
But we can definitely beat them up badly, no question of that.
As for legal action, it ain’t taking place in the US, that’s for sure. However, if it takes place in their operational jurisdictions, it can AND will have a very big impact on their ability to do business in the future.