Yes. For 2 reasons:
1 - CNC is on the order of a magnitude more expensive than additive 3D printing, which will only go down further in cost as technology advances. CNC, well, its already advanced to the point i dont see any reduction in costs. Non CNC hardware would be less costly, but would require an even higher investment in education ( see point #2 )
Manual, used milling machines can be had for around $1000, if not cheaper.
2 - 3D printing requires no special skill or knowledge, unlike subtractive machining. You load it with plastic or resin ( a simple operation ) and hit the print button then walk away for a few hours. When you come back you have a object.
Next question?
Odds are, anyone making the investment and effort to first buy a 3-D printer and then look for and print firearm blueprints isn't just going to be plugging the machine in, hitting print, and walking away. They are going to be tinkering, playing with it, learning how the printer works. If they can do that, they can learn how to use a manual milling machine.
Oh, and Booth (assuming you mean the Civil War Booth) was an idiot driven by ego who thought he could be a hero, not a patriot. Lee and Jackson were patriots. And I say that as a Southerner.