The FBI wants Apple to make a master key. Apple does not want to. Ultimately, it will not matter because encryption is evolving and will make the argument irrelevant.
The computing and telecom revolution shifted central control to individual control, from centralized computing to distributed computing. However, encryption has lagged behind. Large-scale encryption is still centrally managed. Cryptographic locks and keys are issued and managed by huge hardware, software, and service providers like Apple, Microsoft, Google, and Verizon.