I realize Epic is hardly a sympathetic company in this to many gamers, and their motives are pure profit and control of their own cash cow platform. That said, Apple is demonstrating about as much bundled-product market control as a company possibly can. They're preventing access to a whole ecosystem over a single product, and they can't even argue their ecosystem is vertical since individual TVOS and iPad devices can run without phones. Sure, Epic isn't on TVOS yet, but they could be...but only if Apple likes what they do on iPhone.
IF Apple is dominant enough to be subject to Clayton Act controls, this sort of cross-product behavior will most certainly prompt that scrutiny. The fact that the developer program is a "single product" backing them is irrelevant when the consumer products are separate. Epic is making a bold move, but I think it's a very well-timed one.