If I were the NSA, I would publicly ream Apple about the fact that I can't access the encrypted data on iPhones.

I would privately thank them for putting in another backdoor that actually lets me read all the data I want from them.

It's a win-win. Apple gets to look like a privacy crusader. The NSA gets access to all phones. And best of all, iPhone users get to believe that their phone is unhackable, so they won't take the same precautions to hide their illegal activities.