[rbanffy]

> and it never will be connected to any network

That you know of. It might still connect through other TVs in the vicinity using hidden access points, and reach the internet through those for automatic updates and telemetry and, of course, malware.

[nolist_policy]

Do you have a source for that?

[rbanffy]

The best I could find was Samsung TVs connecting to a nearby unsecured hotspot (some routers used to have that by default).

OTOH, if during setup you agree to them sending telemetry, they might just use a cheap cellular modem with arrangements with local telcos for low-traffic data connections with a lower QoS than telephony, the same way some cars do OTA updates even though you don't give their on-board computers access to your phone or home.