The worst thing my TV can do if hacked is stop working completely and forever.
If you don't want to use your WiFi features in your TV or your fridge then simply don't enable the WiFi. Problem solved.
The mass attacks on IoT devices has been against devices that can be directly addressed from the Internet, not devices that are sitting behind a firewall.
I can also freeze to death if my dumb furnace stops working. I don't fear that either, not because it couldn't happen but because I understand that if a furnace stops working I need to call someone to repair it and find a warm place to stay if my house gets too cold.