[mschuster91]

CNC literally stands for "Computer numerical control". They're like the OG 3D printers, they just work subtractively than additive, and at much much much better precision.

You absolutely need computers to control them and loading up models via USB sticks becomes annoying rather fast, so naturally the control computers are network connected.

[swatcoder]

"Network connected" or "conveniently programmable" !== "Internet connected"

It was a rhetorical question. I'm sure the GP knows what the machines are and why they might need some kind of convenient data supply.

Both manufacturers and on-site IT teams have simply gotten cavalier about internet connectivity, network isolation, automatic updates, etc -- convincing themselves that the catastrophic risks that come along with these processes will either not happen to them or will only happen when someone else can be blamed.