Just don't connect your smart TV to the internet. Those saying running a dumb TV with a dongle is just as privacy invading are wrong. Some smart TV's use content recognition to send back everything you watch to the manufacturer. Viewing times, gaming, music, air TV. They can see everything your screen can and it's terrifying.

With dongles, they can only see what the dongle can. Not my gaming sessions or watching local games over the air.

Beware, some smart TV's will also try to get an internet connection over HDMI.