Trannies, commies, tranny commies, and autists.
There are some absolutely sound guys doing 3D printed firearms stuff (RIP JStark) from what I would consider the correct motivations (can't stop the signal, in the spirit of Philip Luty) but theres also a lot of people looking for autistic personal glory like derwood.
And then you have the mentally ill men in frocks who are convinced they need 3d printed guns to bash the fash because White Nationalists are going to come for them any day now to take away their right to late-term abort black babies from their theoretically transplanted wombs. They need 3d printing because they spent their gun fund on DSA merch, bathtub oestrogen and ugly flags. Fuckers are worse for flags than Ulstermen, and absolute drama queens.