What makes a 3D printer different from a lathe or a CNC?
Yes, you can buy old Bridgeports and Pacemakers on Craigslist, or cheap mini-mills and mini-lathes at Harbor Freight, and run them in your garage, and yes, those would be infinitely more valuable in the making of a firearm. No, this law won't prevent someone clever and determined from building a 3D printer with some aluminum scraps, an Arduino, and a few steppers. Similarly, those ITAR PoA forms don't prevent me from buying some servos and bearings from AliExpress, bolting some steel together, and downloading LinuxCNC to make a 5-axis machine that ITAR would say could be used to enable nuclear proliferation. Many in the industry [1] agree that all these restrictions are ineffective and harmful.
The good news for this law is that while a nation state can probably devote a couple engineers and dismantle some obsolete equipment to build a custom 5-axis mill, a New York gangster is more likely to be deterred by this obstacle. But whether these restrictions are completely ineffective political posturing, an opportunity to add a charge to a separate conviction, or an obstacle in front of would-be criminals that is actually effective at reducing crime, is a social question, and unfortunately answers probably depend more on your political preferences than on anything measurable.
[1] https://www.bis.doc.gov/index.php/documents/technology-evalu...
I just don't really see another really good reason for well paid people to be spending their time making a fuss about things that practically don't happen, especially compared to the ease of procuring a "real" firearm.
However it is seemingly pretty common for lobbyists to weaken consumer's positions even if it doesn't bring a tangible, concrete benefit, and seems merely...vindictive/petty.
Or driving to NJ or PA and buying one there.
Designed with the explicit intent of containing no parts that are regulated as firearm components in Europe. Including the barrel, which is manufactured using 3D printed jigs and a bench top power supply.
These are in active use right now, most notably by anti-junta rebels in Myanmar, who have literally been running print farms in the jungle to produce them.