Yeah, I think the best way to phrase it is not "risk free" but "easily mitigatable risks with basic safety precautions and PPE". You just have to be disciplined about the precautions, and then even teenagers can do it safely.
> What exactly you think are hazards in 3D printing? And low-voltage electronics?
Fire (have your dry powder/kitchen fire blanket handy). Minor burns (hot-end, molten plastic, soldering iron, solder itself, hot components or PCBs). Not really more dangerous than cooking - I'd consider leaving a 3D printer unattended but if you leave a deep fat fryer unattended that can go very badly wrong.
Snipping off through-hole leads produces annoying metal fragments; if you're not already wearing glasses, wear eye protection.
> What exactly you think are hazards in 3D printing? And low-voltage electronics?
Fire (have your dry powder/kitchen fire blanket handy). Minor burns (hot-end, molten plastic, soldering iron, solder itself, hot components or PCBs). Not really more dangerous than cooking - I'd consider leaving a 3D printer unattended but if you leave a deep fat fryer unattended that can go very badly wrong.
Snipping off through-hole leads produces annoying metal fragments; if you're not already wearing glasses, wear eye protection.