I just got a new TV and agonized over how to get one that was dumb. I wasn't confident that it would be sufficiently dumb at the time of purchase, but I got a TCL QM6K. This was incidentally recommended by the 4K TV subreddit as one of the cheaper "good" TVs that you can buy this year, which I was glad to read, because I don't particularly care about agonizing over TV hardware details and I was glad to outsource that train of thought.

I set the TV up and was immediately pleased. The first thing it did was ask me if I wanted "smart" or "basic" mode. I selected basic mode, skipped the network connection, and disagreed to as many policies as it would let me. One week in, it hasn't nagged me a single time to connect to the internet or tried to push any other BS on me. I have it hooked up to an Apple TV and my Switch, and it seems to just work.

So yeah, I hope I'm not jinxing something here, but TCL was a great way to go for a delightful dumb TV experience.