Ol Gramps

This stretches just past my knowledge but I think that the hack would be to your router. I think some Smart TVs may have had weaknesses in login with leaks but I don’t think that would keep you from connecting with your WiFi or with an Ethernet cable.
You can always use the Smart TVs for lots of free sites like YouTube. But if you don’t ever want to use the internet on it, don’t bother.