The reason it matters is because Epic's entire theory of the case involves Apple having a "monopoly" over the specific sub-market of "iOS app distribution". The

The reason it matters is because Epic's entire theory of the case involves Apple having a "monopoly" over the specific sub-market of "iOS app distribution". They've intentionally defined this market very narrowly because they know Apple does not have an actual monopoly in the smartphone market. As the judge pointed out yesterday, Epic has "created a failsafe definition". Because they have defined a single product market, Apple by definition has a monopoly over their own product. But assuming Epic's theory is true, it would have been true from the very start of the App Store, back when Apple had barely any market share. Of course, it would have been absurd to complain in 2008 that Apple was unlawfully maintaining its monopoly over "iOS app distribution", which is why Epic's lawyer largely dodged the question during the hearing yesterday.