Such technology is of course a danger to corporatist as it would allow people to gain items that they value or need without having to pay something to existing corporations. It is also a danger to the socialist as people might actually learn to and be willing to do something for themselves instead of being a slave to society.
The only reason to denigrate and fear such a technology is if you are a staunch supporter of either the corporate slaver or the society slaver. For those of us who value freedom, such inventions and their availability are some of the greatest things mankind can create or offer. Empower the individual, not a corporation or some mythic definition of "society".
Be sure to work hard and get lots of overtime. People on welfare want more steaks and free upgrades to smart phones with unlimited data packages.
Numerous people have given you even more numerous answers and you've just kind of thrown a temper tantrum about them all.
I imagine the biggest advance in 3D printing will involve food.
I just don't see how it's going to be in every home anytime soon, and, the 3D printed gun is an absolute failure, unlike the 3D printed house, organs, and the above cited 'magic arms'.
I see no company trying to market the 3D printer to the average person.
No Lives Matter