Did your Roku TV decide to strong arm you into giving up your rights or lose your FULLY FUNCTIONING WORKING TV? Because mine did.
It doesn’t matter if you only use it as a dumb panel for an Apple TV, Fire stick, or just to play your gaming console. You either agree or get bent.
I have a Samsung S90, and I was able to disconnect from my network after the initial setup. I also set it to default to the last HDMI input at startup, so I never see the TV OS.
I feel like this is subject to change, but a smart TV without an Internet connection seems to still be an option until they take it away.