Apple CANNOT afford to stay ahead of the hackers. It took them awhile to hack it after it was released, but now that people have a handle on the phone, now that tools are available on the phone for hacking--basic programs like ssh, etc., it will take less than a week for a company with some money, or for that matter, a bunch of nerds with code.google.com, to workaround their stuff. Just wait for it on the ringtones. They'll have a new hack before next monday, and that's not even relevant--iToner, which doesn't cost all that much money, still works, so they haven't broken custom ringtones completely even with 7.4.2. And regular, honest users are going to start getting really, really annoyed with constant updates that do nothing but break hacks they aren't using.
If apple updated iTunes to brick your iPhone, someone would hack iTunes so that it didn't do that--e.g., denying it a network connection to phone home to apple to check out the phone. But that's not even the issue--that kind of crap is just BOLLOCKS to regular users who aren't hacking, or--users who are hacking (like me) but don't have their phones unlocked or anything... how will they tell the difference?