I loathe to make the slippery slope argument but they're not going to stop at requiring you to monitor your 3D printer so you don't print guns.
If they can claim simply because something is in computer code that is not considered free speech, then your PC is prime real estate for the government to spy on.
This is like asking word processors to report everything back to the government so that they can make sure you're not writing something illegal.
"But I don't do illegal things," I hear you say. Not yet you don't. That day is coming.