Just don't connect it to an internet connection. Although, I might add don't buy one that requires you to connect it on first use (I returned a roku a couple years ago because of this BS, since at the time I just wanted to use it to add netflix to my older TV, and it insisted I add a credit card before allowing anything else).
If you've already gone down this path, just block it on your wifi hotspot/etc. I've got a pile of ways I block things, from wifi blocking, nameserver blocking, to full blown firewall rules blocking IP ranges.
Solves untold grief too, no longer do my windows machines update on their schedule, they don't report usage metrics to MS/etc. Same with my LG tv, it doesn't get to talk to LG services except when I allow it (which is rarely). It just has some generic LG backsplash on the left hand side where it has in the past wanted to display ad's (although they backed off it at one point, but by then it was too late and lost its privileges.
Probably, but there's a caveat they reset the settings anytime. Here, it's been discussed that they'll eagerly connect to unsecure wifi: https://news.ycombinator.com/item?id=25275350
I think that statement needs the caveat that that thread discussed with the conclusion that it's a myth (which as far as I can tell originated on HN), and that there was one single post on Samsung support about a TV connecting to a neighbour's WiFi, which unless someone can reproduce I think we have to assume was their kids or guests doing at this point.
It's the same with smart phones and laptops too. The first feature that seems to have 'worse' specs too is the screen (terrible color gamut and accuracy, only 1080, IPS instead of one of the OLED varieties).
