[gpambrozio]

If you try hard enough you can always find a piece (or many) of code that will "brick" (using your definition...) your device (whatever that is). I don't consider this a bug, or not a serious one at least.

And in this case Apple's approval process could protect the consumer. They would never let something like this past the gates.

[DrJokepu]

If a sandboxed application can get the sandboxing environment into a state where the only way to get the sandboxing environment working again is by restoring it from a backup, that is a serious defect in that environment.

Also, since this issue is very trivial to trigger, it's not very difficult to hide the triggering mechanism in a malicious application in a way that even a reasonably thorough source code inspection would not necessarily spot it. See also: The Underhanded C Contest.