I do this, but increasingly modern TVs complain about not being connected to the internet in general. Usually once every day or two I get a pop up on my Samsung 90F complaining that network access of required for some feature that seems to run on a timer.

This is the right solution. I would be tempted to go one step further: disassemble the TV and remove the WiFi card, antennas, and other unneeded hardware such as microphones or cameras. Same treatment as modern cars with cellular modems.