Once I verify a home video product works as intended I remove its network connection and never connect it again. I then leave its static ip address configured and block any traffic from it on the off chance it’s ever connected again. The sole exception is my PlayStation 5. I use apps on it for all streaming.
Even some cheap Kindles came with a SIM card. I expect this to happen if enough people block ads on TVs. (They'll probably promote it as a "backup connection" or something.)
They didn't put SIM cards in there to spy on you. They were always an opt-in (at additional cost) option for a better user experience.