Don't believe that using an external device helps -- the TV can detect what content is being played by sampling the video stream and creating a fingerprint. They can compare to live tv streams to detect channels, and static video files to detect movies/tv shows -- even the menus and cutscenes in video games can be detected.
Also note that disabling WiFi isn't always helpful - some devices expose ethernet over HDMI which the TV will use to phone home.
Also note that disabling WiFi isn't always helpful - some devices expose ethernet over HDMI which the TV will use to phone home.