I make a living in digital marketing and analytics. I can tell you that these TV makers have more data than ever, and sell it to 3rd parties for advertising targeting purposes. This is something you agree to when you unbox the TV and set it up. I believe Vizio is one that does this the most, but they all have some version of it. Things they capture and report back to advertisers:
- Time spend watching
- Time on a channel
- If a commercial is seen
- If the commercial is skipped or channel is changed
- The a commercial is completed
This is all known with geolocation and timestamp.
As an advertiser, you can then pay 3rd parties to get ratings from this.
- How many people saw the ad, if they completed the ad, what shows they were playing alongside, etc.
Additionally, aside from your typical broadcast television, you also have streaming devices like Rokus which allow for 'addressable TV' meaning that the advertiser knows more about who they're targeting and then show ads directly to them (where traditional TV targets time slots and shows)
With that in mind, all of this is done all over the internet and is only new to the TV world. If you are a user of the internet, you're already being tracked to much greater detail than this... so I'd say: if you 'trust' the internet enough to use it, then I'd not worry about your TV.