You can make a functioning firearm with a $600 3D plastic printer - with features that used to cost 1000 times as much just 15 years ago. There is now price pressure on the 3D metal printers that should also bring their prices down.
If the curve follows what the 3D plastic printers did, there should be a ‘small shop’ version available for about $10K in about 8-10 years that can replicate this.
One thing about those reproduction buttons - some of the cheap ones are capable of surprisingly good resolution, but you must have exceedingly detailed original data for them to work off of and most people doing repops with them don’t.
As compared to the output from a $600 3D printer... one could currently make what I would actually consider an actual “functioning firearm” quicker, cheaper, and more durable using parts that anyone can find at your nearest home improvement or hardware store.
It is of course currently possible to produce high quality firearms parts at home using relatively inexpensive or homemade CAM Milling Machines. I doubt whether anyone on the Philadelphia city council has even a rudimentary knowledge or understanding of gunsmithing.
I reload my own brass so I have a good understanding and respect for the pressures created by even small caliber pistol cartridges. It is a pastime that requires precision and attention to detail to avoid catastrophe. A couple of grains (1 grain = 0.06479891 grams) too much powder and a perfectly good high quality pistol can blow up when fired. I do not believe that the output from a $600 3D printer is going to be reliable or predictable enough anytime soon to safely be used as a firearm.