It wasn't a "split" decision. Apple won 9 of 10 rulings. Epic won 1.
While technically that is a "split", it's not what it sounds like. Developers can now happily incur the expenses associated with collecting payment and marketing their junk. This will benefit Epic and other large developers.
However, the judge also ruled that neither Apple nor the App Store are monopolies. Thus, Apple can now only be called a monopoly by legislative fiat.
Epic will now route users to their own payment systems so that they can do the gouging.
EXCEPT!!!
The judge also ruled that Epic is still in breach of contract and must pay Apple a nice some of change, and Apple is in no way commanded to even let Epic back on the App Store at all. So, they can—at Apple's leisure—go suck a stick!
Oh, and Apple will come up with another way to collect their commission, likely through an increase in expenses for developers to even use the API's, Xcode, etc. That $99/year thing is likely going to go bye-bye for developers who want to leverage Apple's work for close to free (by giving away free apps on the store and then routing users to their own payment systems). $99 may become something like $9999.99—or more—for the titanic Epics of the world. Or, Apple will institute a per-download processing fee that could put a lot of smaller developers into crash-mode. If it costs Apple 50 cents to move an app, and your app is currently free, then "free" is going to become a 99-cent app that wasn't even worth it when it was free. In other words, you're out of business.
All in all, I think the judge made a reasonable compromise. Apple can no longer prevent you from leading your customers outside the App Store, and you get to find out how expensive that can be.
