No, it isn’t. The password hint bug, for example, was “only listening to Apple” in the narrow sense that the OS wouldn’t let you run your own implementation of

No, it isn’t. The password hint bug, for example, was “only listening to Apple” in the narrow sense that the OS wouldn’t let you run your own implementation of password hints or login. But it’s not a backdoor. There are plenty of built-in features that aren’t configurable, which is fine and good. Because most people have no idea what those things do, most of the rest shouldn’t touch them, and leaving them as configurable or editable opens up a whole class of malware.