People are reading too much into the judge's comment. The original order was signed by a Magistrate (a kind of "junior judge"). Apple (as was its right) appealed the Magistrate's ruling to the District Judge. What the judge said was that, since the order was on appeal, it couldn't be enforced until that appeal was decided. He didn't say that it was never valid. Magistrate Sheri Pym is the judge who would be hearing the case, and the Magistrate Judge who signed the agreement. I agree with what you said, though.
From what I've been reading about the potential to hack the phone so far, it would seem that if you care about your phone's privacy, you're better off upgrading to a 6 or better.
Something else that might be useful is software on the phone that you could set it up so that if x amount of time has passed without that software being accessed, that the phone would be wiped to factory settings.