There was another thread with a paywalled article, but here's the actual study that found that smart TVs use "automatic content recognition" to build an ad profile for you based on what's on your screen... including HDMI content streamed from a laptop, game console, etc. Yikes.
At a high level, ACR works by periodically
capturing the content displayed on a TV’s screen and matching
it against a content library to detect the content being viewed on
the TV. It is essentially a Shazam-like technology for audio/video
content on the smart TV [38]. ACR is implemented by all major smart TV manufacturers, including Samsung [9] and LG [55 ].
Our findings indicate that (1) ACR operates even
when it is used as a “dumb” display via HDMI; (2) opt-out mecha-
nisms stop ACR traffic; (3) ACR works differently in the UK as com-
pared to the US.
So it seems like you're opted-in by default, but you can stop ACR traffic by simply configuring six different options on Samsung, or eleven different options on LG.
Oh, and this doesn't seem to happen when you're using native streaming apps like Netflix or Disney+, because hey, they wouldn't want to infringe on those companies' rights by spying on them, right?
What happens when there's an open Wi-Fi connection close enough for the smart TV to connect to?
No idea. My closest neighbour is 250 m/820 feet away, so not something I need to think about.
You’d be surprised. I have one neighbor across the street and my next closest is a quarter mile up the road. I still see multiple Wi-Fi signals to connect to, 2.4GHz wifi can travel way farther than you might think.
Best to let it have an IP but block WAN access so it can’t leave the home network. This also keeps the TV from complaining about not being connected.
There's probably lots of situations in anything but rural environments where open Wi-Fi networks are either already available, or highly likely to be. Dorms, apartments, anything like that becomes a mess.
Yeah. I’m in the rurals and at any given time can see between 5 and a dozen networks. Years back when I was apartment living, there was a ridiculous number of networks in range, couldn’t even give you a count.
If you’re curious and have an android phone or tablet, check out WifiAnalyzer. It gives a graphical view of nearby Wi-Fi networks, channels they’re on, signal strength, and so on.
Your not that rural if your seeing that many wifi networks.
Okay. I live in a town with a population barely over 2000 people, the paved road ends at my house and continues on as dirt roads, I'm surrounded by miles of empty lots of wild growth with a few houses interspersed here and there, and I have one direct neighbor across the street with the next two closest neighbors being a quarter mile up the road.
I guess I don't understand your definition of rural then. Or you don't understand just how far wifi signals can travel when there are no obstructions, or that people can have multiple network SSIDs in their home (hell, I have three, one for 2.4 GHz, one for 5 GHz, and then a separate 5 GHz for a work network). Rural doesn't mean tech illiterate.
Edit - and to be clear, most of the signals I see are probably too weak to be usable due to attenuation, but I can pick them up all the same via Wifi Analyzer. How many networks I see is dependent on the device used. Currently my mini-PC only sees my networks, then a Roku somewhere (probably neighbors across the street) and another single network at low strength, but it varies.
I used to easily see dozens or more networks in the city if sniffing for them. Your PC's wifi won't list all of them, just the strongest signals and there will still be many because city life is saturated that way.