Afaik they cannot ignore a ruling. And they don't need 30% fees for maintaining IOS ecosystem - when you buy an apple phone for $1000, you pay Apple enough for it to maintain its AppStore.
Also they earn money from AppStore advertising (which apps out of the millions should the small screen show); so maintaining AppStore should not be a problem.
This doesn't apply in this case because Apple is not stupid. They are not gonna ignore a court ruling because it will land their execs in jail.
Rather than that, they will use legal means such as appealing the ruling. They are a 2T$ company, and they will try their best to use their money to change this decision in their favor.
Because that’s not how the law works. Sure, they can technically ignore the ruling, but they’re opening themselves up to a whole host of lawsuits, and any judge in those lawsuits would not look favorably on Apple.
"Apple must allow the use of third party payment processors" does not mean "Apple cannot enforce any other rules against apps using third party payment processors". If they decide to go on a harassment campaign of petty violations against third party payment using apps or put undue requirements on them, those parties can complain to the courts and likely succeed. If the third party payment provider is stealing credit cards or obviously malicious behavior in some other area, Apple would likely prevail when pointing to that as the reason they banned them.
> What's the penalty for Apple just ignoring this ruling, if any?
In addition to whatever penalties are available in law for the act outside of the ruling, they would also face additional consequences for contempt of court. And its generally easier to prove a violation of the order than a violation of the law justifying the order.
>If any part of this Order is violated by any party named herein or any other person, plaintiff may, by motion with notice to the attorneys for defendant, apply for sanctions or other relief that may be appropriate.
The penalty for contempt of court is often incarceration. Note that the order enjoins not just Apple the corporation but also Apple's officers. It would be highly unusual for the CEO of a major corporation to openly and defiantly flout a court order, but if it happens, he can expect to be arrested for contempt.