If that is so, why did the FBI persist? If the govt had the ability to get into the phone, why didn’t they just do it? Am I missing something?
Yes, you are missing something. They wanted Apple to install a continuous backdoor. I sided with Apple on that point. That, and this wasn’t about decryption at all. The Internet has a way of letting people think they know what’s going on and that they know all about it. Fact is, this was never about decryption.
P.S. The FBI and the NSA do not have a productive relationship, so the FBI doesn’t have access to anything and everything cryptographically related.