Of course they were. They knew exactly what Apple would do because Apple has never been shy about telling developers what will happen when they do stuff like this.
Whether or not they are breaking the law, they are about to have every single aspect of their market behaviour put under the microscope.
They don't need to break a law to be found to be operating anti-competitively.
I'll let Epic Games know, so that they can drop the suit and save themselves some vbucks.