Do you think an Apple TV and a Walmart special TV have same risks? I don't. I give the Apple device my network credentials and the TV never sees them.
Another device might not give the free reign for all shitty malware like they do. Apple TV for one wouldn't.
No thanks, I prefer owning my media in a way that corporations can't just take it away whenever they feel like and where I can use (open source) players of my choosing.
But the replies are missing the point that most people aren't techies and won't go do this. They go to big box store, buy the tv, ask if it has netflix, done.
They won't (and shouldn't need to) install a ATV.