The requirements list is very interesting.
For example:
> Meet the following functional requirements to ensure your app is using a web browser engine that provides a baseline of web functionality: Pass a minimum percentage of tests available from industry standard test suites: 90% from Web Platform Tests and 80% from Test262
And:
> Program security requirements: You must do the following: Use memory-safe programming languages, or features that improve memory safety within other languages, within the Alternative Web Browser Engine at a minimum for all code that processes web content;
Is WebKit written in C++? That language certainly isn't "memory-safe" (I am not dumping on C++ here!). I assume that Apple uses fuzz testing and static analysis to find memory safety issues. So... does WebKit pass this rule? Hmm... And, are there any browsers written in memory-safe languages? I assume they would be too slow (Java, C#, etc.) I'm not sure if Rust is considered memory safe here. (Can you have null pointer exceptions in Rust -- dereference a null pointer?)
Large portions of each browser are also written in JS ("self-hosted") at this point, and Firefox now contains large components either written in Rust or sandboxed (via wasm) C.
This rule does seem like an easy way to reject literally every browser other than Servo, though.
But not many people will see it here buried down deep in this thread. I suggest you submit it as a new link to HN though. Very interesting stuff!
Apple points out that the new terms are required for third-party app stores and third-party payments. Not for browser engines.
I'm expecting both Google and Mozilla to make their browsers, with their engine, available in Apple's regular store in the EU.
(And even in the new agreement, it's not half a euro per update. It's per year that contains an install or update. If you update 12 times a year, you're not paying 12 times. You're paying once.)