The Sapienza computer scientists say Wi-Fi signals offer superior surveillance potential compared to cameras because they’re not affected by light conditions, can penetrate walls and other obstacles, and they’re more privacy-preserving than visual images.
[…] The Rome-based researchers who proposed WhoFi claim their technique makes accurate matches on the public NTU-Fi dataset up to 95.5 percent of the time when the deep neural network uses the transformer encoding architecture.
Cameras require light, while radio waves works almost as well in darkness.
A motion sensor is an extra device that needs to be connected, have power and so on.
There are already radio wave motion- and room occupancy sensors where you can specify zones and so on, but if I could have personalized on top of that I’d take it.
Finally, using a thing for something useful other than its intended purpose is kinda fun.