I was dreading my most recent tv purchase (last fall) for exactly this reason, and ended up with TCL google tv. One can apparently setup a google tv as a dumb tv and never sign it into the internet. It acts exactly how I'd want a dumb tv to work now, simply auto uses the most recent hdmi device, or the active one if the most recent one isn't active.
It has never connected to the internet, and it never will. My long term concern is that google will eventually put cell modems in their tvs, and then using my next tv as a dumb tv will no longer be an option. For now though, this is your best bet.
Honest question: why doesn't the dumb TV crowd use old TVs (dunno, 10+ years old) as a replacement? Does image quality difference feel so dramatic? Maybe I don't care about this enough. To me the DVD fidelity was not earth-shattering but fine in practice. I do go to the cinema and see new TVs in stores, so it's not like I haven't seen better, just isn't worth a huge premium for me.
Other things I can think about is reliability of the screen (like dead pixels), and your family if not clued in may think you present as "poor".
Well personally, I use my TV with a PC much of the time and you can't do anything close to 4K/120Hz/VRR on an old TV, you're basically stuck at a static 60Hz 1080p SDR.
I don't see this happening any time in the near future. The extra hardware cost is nontrivial, and there's a software support burden. Cellular bandwidth also isn't free, and probably wouldn't be covered by the value of any ads/telemetry that it carried.
Hopefully? I mean, adding the cell modem is sort of hypothesizing about the future, and if we're already doing that then we might as well also hypothesize that such a future google tv will refuse to display anything from its hdmi inputs until it successfully phones home, and that that happens weekly.
LG + never log it in to the internet + an Apple TV box. The webOS UI sucks, but so do all the others apparently, and you never have to interact with it in practice if you use the Apple TV for streaming.
"fine" is a very accurate word to describe Tizen. It's slow and really hard to find things sometimes (why do TVs not have a simple "input switch" button any more?), but ultimately it gets the job done.
You can make Tizen much faster by manually uninstalling the Samsung TV Plus app. It runs in the background constantly. "Much faster" is still slow overall, unfortunately.
1. Remove the few pre-installed apps except the HDMI inputs you want.
2. Then disconnect wifi.
As long as the device you turn on does HDMI-CEC (which almost everything other than a PC does) it will automatically switch to the input that your device is connected to. If it doesn't, you just have to click on the input you want to switch to.
It has never connected to the internet, and it never will. My long term concern is that google will eventually put cell modems in their tvs, and then using my next tv as a dumb tv will no longer be an option. For now though, this is your best bet.