55" is the 'sweet spot' for value. Within that, either (1) just buy whatever and don't EVER connect wifi (if possible, cut the antenna); or (2) if you can find it, get a signage-targeting system which doesn't come 'smart' with Android, this means you can rely on longer use and no surveillance (eg. no microphone) however you may not get the same visual results as a TV-market screen.

Option 2 is a frequent HN recommendation, recently I tried it and bought an ~AUD$400 55" signage screen which would be ~AUD$1000-1200 for a lower-end Android device with surveillance. The visual caliber is not perfect however I can rest easy knowing it's not recording all my household conversations and uploading it to the advertising databases. For the price I can buy something 3 times over before I'm at the same capital outlay, and get upgrades along the way. As my main requirement was 'big' (had to be comfy to watch on a relatively distant couch) this basically checked all the boxes.