It even predates 5G by a long shot, I recall anecdotes running the news headlines about some folks claiming newly installed (2G? 3G?) cell towers were causing them debilitating headaches, and covering walls and windows with tin foil made it better. It was later revealed that while the tower was indeed up it was entirely unpowered the whole time but that bit of news of course did not make it to the headlines.
But ironically those people were truly and seriously getting headaches and tin foil really made it better. People get to experience what they believe deep in their subconsious. See the Nocebo effect: https://en.m.wikipedia.org/wiki/Nocebo
Having 2 doctor parents and some amount of experience in the field of hypnosis, I can say these sort of things happen all the time to people.
Yes I don't think people realize how widespread stuff like homeopathy, cellular EM scare, antivaxx are widespread in Europe and the rest of the world. The US gets the spotlight but in other countries those opinions are often not even controversial (especially for less obvious stuff like radio waves etc)