They could put an IR camera right next to the remote sensor. Since it's behind a glass that is opaque to visible-light you wouldn't even know the camera's there, and if you put tape on it your remote wouldn't work anymore.

Thank you for giving such great ideas for free to CIA, I just can't help to wait until it's implemented in my next smart tv /s

>Since it's behind a glass that is opaque to visible-light you wouldn't even know the camera's there

If it's opaque to visible light how does the camera produce an image?

>if you put tape on it your remote wouldn't work anymore.

Not really? You just have to be more careful placing the tape. Besides, nowadays many smart TV have app remote controls, or RF-based remote controls so the IR sensor being blocked is a non-issue

> If it's opaque to visible light how does the camera produce an image?

It isn't opaque to infrared light though. The image is still high enough quality to make out people, it looks funny but it is good enough for their purposes.