So they can (and sometimes already do) insert a SIM card in the TV and use any of the consumer 4G/LTE/5G networks out there which your phone connects to. Why are people hypothesizing that Vizio will ship a $250K 5G base station to your house?
because if setting up private 5G networks becomes cheaper and open to any business then the chance TV manufacturers consider putting 5G base near enough your house.