That was kind of a canary citation to indicate that there's growing sentiment towards banning the 80% lowers, though if I understand your objection correctly, you are right in asserting that suggestions to ban CNC / milling equipment is not predominant. That said, I would swear that I saw some state making mention of regulating the purchase of drill presses and/or milling equipment to restrict their purchase to those who could show a justifiable industrial need, but I can't remember whether it was federal, state, or if state, which, nor can I find such a citation in my naive Googling efforts.

Regardless, the sentiment definitely exists for banning 80% lowers, and that is in fact the core of Kevin de Leon's "ghost gun" legislation, though that does not necessarily extend to banning the equipment required for milling them to functionality.

Note that these sources are biased, so take with salt: http://dailycaller.com/2013/08/14/federal-gun-bill-would-ban...

http://bearingarms.com/california-legislator-targets-80-lowe...