you use illegal methods to get X without a warrant. but you can't use that information legally. so you use your knowledge of X to find a legal way of learning X, after the fact.

then you go to the courts saying you found X the legal way.

but you didn't.

But the reason most of us care about having our data encrypted is not actually because we are committing heinous felonies, and want our phones to hide the evidence from legitimate cops (though of course sometimes that’s the case).

It’s because we don’t trust the authorities to follow the law. If they can crack your phone legally, they can also crack it illegally. (Say, after seizing it within 100 miles of the border, which they can do any time they please for whatever reason (including no real reason)).

So even though this ability isn’t necessarily illegal in and of itself, it’s certainly of interest to those of us who are concerned about the threat vectors that are presented by government forces that do engage in illegal practices.