PS: I'm also open to smart TVs that can be "jailbroken" or severely restricted to remove all their "smartness".
My use case: Watch shows streamed from my laptop via HDMI, play games, etc.
Most TV's won't freak out if they lack an internet connection and are still fully functional (outside of services that require internet), and many can be updated via firmware on USB thumbdrive over sneakernet.
This is also more futurepoof - I have a relatively ancient (in TV timelines) Vizio that is so old that none of the apps were working with modern services (and even when they worked the were slow/laggy), so I just unplugged ethernet and drove it from other HDMI sources.
If only this was true.
Some (if not most) check for a connection on power up and "freak out" by launching into setup if there isn't one --- unless you run the TV in store/demo mode.
Backing out of setup on every startup is possible --- but it is often a multi-step process that becomes extremely annoying. Basically, they try to frustrate you into connecting --- unless you run the TV in store/demo mode.
I have a lower end Hisense 55" QLED model from Costco (roughly $250) that I run in this "dumb" store mode connected to my own "smarts" that I control.
Smart TVs are actually cheaper --- which make no sense until you realize they are counting on recurring revenue from privacy invasion. They try to strong arm you into connecting the TV to the internet --- unless you run the TV in store demo mode.
Also, the picture quality on lower ends models differ from the more expensive ones primarily because their bightness, contrast and color saturation controls are artificially limited --- except when run in store demo mode.
So my solution is to buy a low end smart TV and run it in demo/store mode without connecting it to the internet. Whereupon, it it will act just like a dumb TV with the brightness and contrast jacked up to simulate the more expensive models.
The commercial digital signage displays are very expensive and not as good for normal home use cases.
There's some comments in this thread about the TVs "freaking out" if they aren't connected to the Internet. I haven't run into one where that can't be disabled, and I've messed with a lot of TVs.
Datapoint: my house is blanketed with recent-ish TCL and Samsung models and I don't have any issues with them. While they were much cheaper, I prefer the TCLs, if it matters. I have Apple TVs plugged into them.
Added bonus: my home network blocks all traffic to and from the TVs. Therefore they are as dumb as they can be.
If it doesn't work without network, take it back to the shop. "TV does not work without wifi, I have no wifi. Please sell me a TV that works without wifi." Repeat if necessary.
At some point these fucking snakes will hopefully get the message.
It can be annoying, but just running an HDMI cable from your device to the TV can be a simple solution.
You could use a laptop with no network connection and load it up with videos, or or just run your various streaming services in their own Firefox container[1].
You can add a TV tuner later on if you decide you need to access basic cable. (I got one back in 2016 to watch the debates).
[1] https://addons.mozilla.org/en-US/firefox/addon/multi-account...
[2] TV tuner https://en.wikipedia.org/wiki/TV_tuner_card
If you do want streaming apps, Bluetooth, wireless sharing, etc, you can buy a plugin box/dongle. E.g. a Chromecast, Google TV, or a full-blown AVR.
https://pro.sony/en_FI/products/professional-displays/produc...
Look for old, used TVs for sale. Something 2005-2015 that was highly rated (mostly plasma, but there are some LCD) is still a very good dumb TV in 2025.