This is scheduled for 2024 via IEEE 802.11bf in Wi-Fi 7 Sensing, it's passive radar that passes through the walls of homes and business, e.g. neighbors or adversaries can identify humans, activity, typing, combination locks, etc. Anything involving motion which causes Doppler shift. Hundreds of papers have been published over the past decade and it can be done with hardware that costs less than $20.

Defenses are either cat&mouse electronic warfare or shielding the walls/floor/roof of some rooms (e.g. research labs in business, industrial systems, home offices, bedrooms) with materials like aluminum radiant barrier or expensive drywall (e.g. QuietRock) designed for RF shielding of SCIFs.

Prior threads: https://news.ycombinator.com/item?id=31561338#31563572