I want to point out, that manufacturing a gun is not "non-trivial".

Given blueprints, (publicly available) or a template and accurate enough measures, a lathe, and a mill, anyone can make a firearm or parts for one in their garage.

Is there reading involved? Yes. But any argument you make w.r.t. The futility of illegalizing encryption is immediately portable to firearms manufacture.

I mean... manufacturing a working modern firearm in their garage is probably much more achievable to the general population than rolling out any kind of encryption software. Anyone with some basic hands-on competency can make a gun.

All you really need is a drill press and some basic tools. People made Sten guns in WWII and that's still a perfectly valid firearm design (fully automatic even) that requires almost no work to make.

Given that I have many, many crypto libraries in many many devices, some of which are heavily modified, chances of me even being able to replace those with broken crypto libraries is like... 0. Many people are in a similar situation, so I don't understand how we could even comply with a law like that if we wanted to (which we don't). So yeah, not only trivial to retain unbroken crypto, but nearly impossible to get rid of it.