Apple owns the code and all it's visibility - you're not allowed to see it.
They don't need a 0 day to compromise your device, they can just choose to do it at any point. You're simply trusting they don't.
And you think not having a the source available hiders security researchers?
It’s kind of what they do.
And you think not having a the source available hiders security researchers?
It’s kind of what they do.