Why can't they simply unlock that one unit, then return it to the FBI? I know that sounds way too simple, but I would think Apple would be able to do this, without revealing how they actually did it. I think it's important that they find out what kind of information is stored in that phone.
In previous briefings on this issue Apple stated the new iOS is encrypted in a way that Apple does not have the corresponding keypair to unlock it. It's not an issue of them being unwilling, it's an issue of them designing it in a way where they are incapable.
That's part of the battle - the State is trying to argue they did it to obstruct justice and are referring to the All Writs Act to enforce their will. Apple really just doesn't want the bad PR and there is zero strategic advantage that isn't overwhelmingly outweighed by the baggage. It's legitimately in the company, and through them the shareholders best interest to position themselves in this way as opposed to being a government proxy. Our current younger generation grew up fearing getting sued for downloading music and paying hundreds of dollars for college texts books just to get an e-code so they're suspicious of everything now, and that is the primary customer for Apples product lineup. Cause meet effect, there isn't much to be confused about here.