Could it be possible that the government want to lose in this case(and in the media) - creating a strong illusion that the iPhone is 100% safe from spying ? How valuable such an illusion would be ?
Eileen M. Decker, United States Attorney
Patricia A Donahue, Assistant US Attorney &
Chief, National Security Division
Tracy L. Wilkinson, Assistant US Attorney
Allen W. Chiu, Assistant US AttorneyThere are dozens if not hundreds of viable methods to obtain this info, FBI is choosing to pursue the court order route instead of any of the other forensic tools available to them.
The simple fact of the matter is that the encrypted data and the key to decrypt it both live in a piece of physical hardware on the device-- no matter how well obfuscated it is, it can still be analyzed and recovered by a sufficiently advanced technical entity.
This is exactly the type of work that NSA TAO exists to accomplish, and they are widely regarded as one of the best organizations of this kind in the world.