1) You’re right; and I hope we don’t get to the point where we need to put every single thing into the safety codes. We are expected to have good judgement. When things need to be added to the safety codes it’s usually after something bad has happened.
2) That many people do something doesn’t make it a best practice (or even a good practice). At least with the other switches you’ve named other rocketry people would know what to do and could do it; with a key switch that ability is denied them.
Key switches are designed to add security, not reliability. I’ve never seen one that has a shock rating.
I can tell that you resent my suggestions. I’ll butt out.
Please no, not resentment! Disagreement,and a little befuddlement. There is nothing more dangerous than forgetting to arm your electronics on the pad, right? And switches that give no indication from a distance that the electronics are not armed could be said to be very unsafe for that reason.
I've read lots of threads where people say that they sometimes forget to arm their electronics at the pad. Thus, the invention of the "remove before flight" tags. These tags, as far as I can tell, only work with key switches, because no other switches have a removable part. So in that sense, key switches are the safest.
I just can't imagine a scenario in which a grounded rocket with a magnetic switch is safer than one with a key switch. I may be the only one with the key, but I also may be the only one with the magnet or the wi-fi controller; but I am also very likely out looking for my rocket with those things in my pocket. I am not expecting anyone to carry my rocket back to the flight line while it is armed, no matter what kind of switch is in it.
Of course, all of this presumes that I have not abandoned my rocket and gone home. But I can promise you that if I find someone else's rocket on the ground armed with a mag switch, pull switch, or wi-fi switch, I am not going to be able to turn it off. I might have a Leatherman in my pocket, but that's about it.