Why go through all that trouble of spoofing MAC addresses or assuming it will always be able to connect to an open WiFi network.

5G connectivity is cheap. You can put a 5G modem in pretty much any device for $10 or less, and pay roughly $2/year in subscription fees. My local water utility with ~900 subscribers pays $2/year for 5G connectivity for water meters, and I have no doubt you can get it much cheaper at scale.

They don't even have to tell you about the 5G modem. It could exclusively be used for exfiltrating data about your viewing habits. It's virtually undetectable and more or less impossible to block. The TV could behave nice on the Wifi, you can block all the DNS servers you like, it would still be able to phone home.