When I bought a Samsung TV a few years ago, I noticed it had "Smart TV" features. I had to laugh at the incongruity of the words "smart" and "TV" being used together.
My DSL is too slow to stream anything, but I did some experimenting. I was able to connect my TV to the internet using Samsung's built-in features. You can subscribe to services like Netflix, watch Hulu or YouTube, or surf the net. But I dislike the idea and I discourage people from doing it. Interesting that B&H has a search filter for TVs without "smart" features. I wonder if people are intentionally avoiding these features when they buy a TV. If I buy another TV, I will, too.
Security is the obvious problem. Samsung has its own browser, which I trusted much less than Firefox, and it's not very good. I have Firefox loaded up with Ublock origin, Privacy Badger, HTTPS Everywhere, and YouTube Enhancer: four extensions for privacy and blocking ads, and they still don't block auto-play video ads. I assume the same problems will exist when you connect your TV to the internet and Samsung tries to gather information about you.
You will also get put on the update treadmill, always having to download something to "improve" or "fix" your system. This is one of the biggest burdens of the Internet of Things that I rarely see anyone mention.
"I can't come and get you. I have to download an update to my car so the brakes will work again."
We know that there are computers and software that "listen", that phone home, and send information back to the mothership without notifying you. So of course the technology exists to have your TV "listen" after it has software in it and after it becomes tethered to the internet. Used to be that suspicion was a sign of schizophrenia. I hope doctors are up on the latest technology.
My mom has to use an ID and password and give it to Intuit to be able to use Quicken, despite not using any online banking or online transactions. When I heard this, I was furious. Even worse, about once a year there is some excuse to "renew", "refresh", or choose a new ID and password, and it always fails, thus blocking her from her own data. She gets advertising and notifications in Quicken because she is now tethered to Intuit. Sometimes she can't even run the program until she interacts in some way with these intrusive messages.
I called tech support and I just swore at the guy, quite unusual for me. I despise Quicken.
OS X 10.11.6
iMac 21.5", Mid 2011
2.8 GHz Intel Core i7, 24 GB
AMD Radeon HD 6770M
Using Apple computers since 1980