Are the cellular providers going to give free cellular access to these manufacturers or something? Consumers aren't going to pay for that. No one's going to buy a TV that requires an additional $30/month for a data plan.
Today that revenue subsidizes the cost of the TV itself, the additional cost of 4G/5G based service for small bits of data is not much. Other options can be LoRaWAN, NB-IoT or other such services since the data transferred is going to be small, primarily analytics. All of these are pretty cheap both to embed in the TV as well as the service, especially at scale.
I actually wouldn't be surprised in the least if this became commonplace down the road. Just open up your new telescreen and bam it seemlessly connects to the 5G/wireless network without issue. You'll get every update, ad, tracking, software automatically pushed to the machine without the need for the user to intervene.
*lifetime - defined as "lifetime of the device", whatever that means. 5 years in and it still works fine.
However, I must point out that a satnav device's occasional updates, as I said, don't use much data: just a multi-megabyte download every few months at most. But streaming constant surveillance data from a TV to the "mother ship" is going to require far more data than that. Multiply this by an average of 1-3 TVs per household, and this seems like a big load on the cellular system.