I don’t think I am the target audience for these products, and have no answers for you, but am curious what these would do above what turning the device off. Is a device that is powered off still reachable? Or is this not about that?

Anyway, on to the non answers, when i worked around wiring that needed to not be affected by interference from adjacent wiring, it would we shielded by aluminum. It was thicker than household foil, and had braiding. The wires could be run with other, non shielded wires, most of which were dramatically different voltages.

I am not a scientist 😅