One acquaintance, after years of trying to work out what was wrong and believing EM missions may play a role turned out to have hemochromotosis (genetic disorder characterized by excessive intestinal absorption of dietary iron, resulting in a pathological increase in total body iron) which is fixed by regular blood donations.
You’re making an assumption here that it was not the increased iron in her body that made them more sensitive to electromagnetic fields. I mean, I’m not saying it’s true or not, but that’s the mistake you’re making in your argument.
I think many people who don’t have EMF sensitivity find EMFs something easy to say is the cause their health issues, but they approach how to figure it out if it is true with zero scientific thought.