I see. Roku, for example, takes screenshots of the TV N times per second (and sends them home).

Remember that it doesn't take much to identify someone: Gender, birthdate, and (zip code?) uniquely identify ~80% of Americans. From viewing habits, it should be easy to fingerprint someone - Chicago Bears fan; strong technology interest; on your city block; likes AI porn with Lara Croft; home during day Sa, Su, Tu, Th; watches YouTube videos about ...