Scientists in Germany have demonstrated a startling new form of surveillance: identifying people using nothing more than ordinary WiFi signals. By analyzing how radio waves bounce around a room, researchers can effectively “see” and recognize individuals — even if they are not carrying a device and even if their phone is turned off.
I suspect it applies to 5G phone signals too (because they are in a similar frequency) so you need to live where there are no nearby 5G masts and all your visitors must use Faraday bags.
So it’s now impossible to prevent them from watching me in my own home without making massive sacrifices and costs?