Not a lawyer but I don't see what else could be true here. I suppose you could say the end users are the ones violating the TOS? I don't think it'll land with any judge, "your honor we just did the reverse engineering (without signing a TOS) and sold it to our users (who did sign a TOS, but didn't reverse engineer), so we're all clean."
During setup, Apple's servers return authorization keys for your device to use.
Seems pretty clear cut to me.
Fortunately, courts aren't computers, judges aren't compilers, and legal code isn't a programming language.
"Authorization" in the legal sense != authorization in the cryptographic sense. You can get a token and still be not legally authorized to access a system.
Accessing a public server using the public protocol it advertises is generally allowed.
It is possible to put unenforceable terms in a TOS, but it's simply untrue that "TOSes are not legally binding."
What do you think is the distinction between a legally binding contract and a TOS?
In a similar vein: has any maker of web scraping tools been sued by a website? I couldn't find anything.