1. The technique is not a practical mass‑surveillance tool
“Resolution and positional accuracy are very poor. It’s more like ‘an approximate bag of water detector’.” – brk
“The paper says, in a somewhat contrived scenario, with dozens of labelled walkthroughs per person, they can identify that person from their gait based on CSI and other Wi‑Fi information.” – avidiax
“This is a controlled environment… it would be nearly worthless in a real crowded environment.” – sponaugle
2. Privacy fears are amplified by the fact that the data is already widely collected
“Wi‑Fi is already part of invisible mass surveillance systems… it’s part of how cell phones fix location, which is then sent to Google, Apple, every app, every advertiser, etc.” – bagels
“Android devices already know exactly where they are even with GPS disabled… Google knows already.” – barrystaes
“The approach described in the article is much different and more interesting, as it's passive and doesn't require any electronics on the individual being identified.” – oasisbob
3. The underlying signal (BFI/CSI) is technically limited and hard to exploit at scale
“BFI is much more complex than simple signal strength… BFI is a high‑resolution, compressed representation of signal characteristics.” – spyder
“The paper had no success correlating across different perspectives – welcome to science reporting.” – ghostly_s
“You need to send specific packets at a high enough rate… it is not useful on normal Wi‑Fi traffic.” – mahrain
These three themes—technical impracticality, existing privacy infrastructure, and signal‑level limitations—dominate the discussion.