Like I said, "nothing to lose" sure they may be able to trace it but by then they are fighting for their life against all odds. Also they could have a "freedom fighter team" where they buy the drones 2nd hand, in bulk, illegally, or just steal them. This would not be a covert operation, it would be a rebel force.
Cheap gps enabled drones are very plentiful on the internet. You don't need to 3d print anything except maybe the parts to hold the bomb. Just need to reprogram them to have them go to a fixed point and trigger a relay with an explosive. It's trivial, and the fact that it is not common for most people with the skills to do it is because they have a lot to lose if they are caught. Once you take away enough rights and liberties that smart techy people have nothing left to lose then you will see more remote drone attacks.
This is the reason the federal government has been trying to ban drone companies like DJI, they are afraid of the cheap throw away bomb delivery vehicles.
I don't print that often but I do have a calendar event to tell me to print something monthly. This could be a nice side project for someone to write a program that sends a print to your printer on a schedule to keep the heads clear. Wastes paper but at least the heads won't dry out.
I think the attempted murder charge would fall on whoever installed the bomb and rigged up the button or the one instructing the person that if they press the button the person will die. The button presser may get away with it with the argument they were under duress.
I wouldn't say that it's entirely eugenics. Most of the point they were making is environmental factors like having uneducated parents that don't enrich the child's life or being too poor for education because the parents were too poor because they had 10 kids. It's where we are headed because they are trying to actively destroy our education system and force people into unwanted births.
Lattes?