This is actually a feature of the Plume wifi mesh devices. https://support.plume.com/s/article/Sense-Live-View?language... It's also available from any other ISP that uses them, or if you buy your own Plume device and a subscription. It's been there for years. https://arstechnica.com/gadgets/2020/03/from-wi-fi-to-spy-fi...
https://staceyoniot.com/the-next-big-wi-fi-standard-is-for-s...
> The IEEE plans to take the concepts for Wi-Fi sensing from the proprietary system built by Cognitive (which has been licensed to Qualcomm and also Plume) and create a standard interface for how the chips calculate interference that determines where in space an object is.
Other firmware sensing capability: https://www.cognitivesystems.com/caregiver/