Like it or not IOS has 2/3rds of revenue in the mobile apps market and how many businesses can afford to leave 46%(0.7*0.66), of their revenue on the table?
It's pretty obvious that epic has goaded apple into punching them. But there's plenty of people who feel it's the equivalent of apple saying you have to give me your lunch money every 3 days or I'll beat you and epic making sure the teacher is watching when they maliciously don't hand over their lunch money (I'll add I'm not arguing that the schools football team wouldn't have much fewer wins without apple, to stretch the metaphor to breaking).
Still, illegal, and that's the question being litigated here.
You can stick anything you want in an EULA but it's not automatically enforceable. If Apple started adding a stipulation that your first-born would be a slave to Tim making iPhones for life, that wouldn't be enforceable. In general you can't sue until there's damages -- so you couldn't sue just for that term existing in the EULA. You wait for your first-born to enter slavery, then sue.
And closing the account is retaliation.
I think people are giving different meanings to words, with moral judgment tied to some of these meanings, and these meanings are causing confusion.
Let's take the word discriminate. Is it wrong if I discriminate when hiring someone? Many will say yes, but because they are thinking of specific forms of discrimination such as based on race or gender. But if I choose to not hire someone because of a lack of programming skill, that is still discrimination, but isn't wrong.
So back on topic. The action of closing the account is retaliation. So the question becomes is it wrong, but to answer that clearly depends upon if Apple's terms are right to begin with and if it is possible to offer someone terms that are wrong to uphold.
What good is a terms of use if that use cannot be rescinded upon breaching the terms?
And if they succeed, then the terms will be worth nothing, and Apple would have to explain why they go around signing illegal agreements that for example allow them to punch people in the face.
If Epic fails, then yeah, the legal terms say for example that the punishment for what Epic did is a punch in the face, and Apple is just enforcing that legally.
What law would you claim disallows limiting payment systems?
I definitely remember cases from the early years of the App Store where people would deliberately sneak e.g. tethering apps into the App Store in the guise of a game, and usually came to public attention when their account was banned.
Epic said "Okay, we agree.", then broke the terms they agreed to, so Apple is closing their account.
This seems like pretty straightforward break of the terms of use to me.
The reasonable way Epic could have proceeded is to have submitted an update with the "third party store" stuff added, gotten it rejected, and then rolled it back while suing Apple.
Instead, Epic pulled a publicity stunt by sneaking it in, specifically so that Apple and Google would remove their app, and then suing, in an attempt to make themselves look like the good guy (which, depending on your perspective, might be true).
It doesn't feel any more mature than goading someone into throwing a punch at you so you can claim to be "defending yourself" when really you were just being a douche and you got what you asked for.