Not entirely a fair comparison. Gun owners might have to deal with some extra process in the acquisition of a tool explicitly capable of sending projectiles at lethal speeds. There is a good reason why some of those hoops might be tied to "crime prevention". Because it is a tool remarkably well suited for it...
Adding such loops for 3D printers would make as much sense as for a bag of sand, because you could drop it on someone... But that's not what it's used for... and the extra hoops should be in proportion.
edit: Have I stumbled on some gun-loving easily offended part of lemmy? Let's see some congruent argument against anything I wrote. I encourage it. Be a brave snowflake.