> Federal wiretap law can compel companies to make it easy for the government to get data via a warrant

Not the same thing. The wiretap law cannot compel any company; only licensed telcos. These companies, in exchange for license to be able to provide such service to general public get some advantages, but have to agree to a set of limitations.

I have my doubts that Apple would be a holder of such license that would make it a subject to such regulations.