If someone, let's say, happened to own a Roku TV and a NAS full of some sort of DRM-free video content ripped from home-video media they legitimately own and have legally format-shifted and backed up, to watch their stuff they'd still have to wade through Roku's enshittifying home screen to access the appropriate media player.
Might not be the exact solution you're looking for, but I run my "smart TV" off a cheap ass laptop. The TV itselfbhas never been connected to the internet.
Absolutely! There is no reason for the TV itself to have access, I'm actually using this TV as kind of an experiment, I let my last 2 roku TVs access the internet, and after 2-3 years they both went tits up. I've heard rumors that they can pretty much be broken on schedule with "updates" and shit. No idea if that is true, But if this TV lasts me a good long while, I will assume it is lol. So far 1 year on this one lol.
I sure as fuck hope not lol. I don't think my TV has that capability, even if it wanted to. If I don't give it access to my shit, its just a big-ass monitor lol.