First of all, Linux expects the user to know what he is doing. The same is true for electricity.
As we see almost every day in the forum, users oftentimes do not know what they are doing.
A warning seems advisable.
While I don't have a real preference for either of them, I think this is a good idea. A similar warning is probably in order for all devices with integrated xDSL modem as well, as the phone lines might carry up to 90 volts (one would hope that $user disconnects their device from the phone line before messing with it, but…).
So nice, actually my new EdgeRouter 4 is connected directly to the 230V AC power line.
I guess that is why most home router manufacturers only use a AC/DC adapter with low voltage to get them CE approved so the customers survive when they lick on the connector or do something else they shouldn’t do.
I got the feeling mostly the industrial and business class network devices are the high voltage devices🤔
There are no real voltage level for high voltage per definition. If it can hurt or kill humans or animals then it is high voltage. That is all voltages that draw more than 30mA through the standardised human body or a animal.
High voltage per the definition of >1000V is the voltage level when the current starts to move as a corona effect, air is ionized and discharge length is 1000V/cm.
In Sweden we did name this from the year 1909 as Starkström (kind of ”strong current” in english) that had the definition of ”all currents that is dangerous for humans and animals”. And in the regulations (was called the “The blue book” because of it’s color) from the electrical agency had three chapters A (common rules), B with safety rules for voltage level under 1000V and chapter C with the safety rules when at voltages over 1000V.
But the definition of ”strong current” was in chapter A so it applied for both chapter B and C. Then someone invented the EU...
The problem is that I am not aware of any english speaking country that made the definition of “strong current” as the definition of dangerous and not dangerous. Instead high voltage became the definition in English.
My reason is that the person should decide if they have the skills to work with mains voltage and only then proceed. There is more too it than not touching things. For example I have seen unqualified people leave equipment that they are working on in exposed state while they go for a lunch break or at home with young children.
Then you are saying: Any mains powered device which requires serial access (and hence opening the case) can not be flashed with OpenWrt because no user out there is qualified to handle mains voltage (exceptions confirm the rule).
Since users usually do not care about being qualified or not, we should at least give some practical advice that helps to avoid the worst.