Cars having 5G connectivity is something that consumers actually want, it’s well documented on the spec sheets and marketing material, and obviously in a car WiFi is not going to work in most places. None of those things apply to TVs.
The linked image shows a module meant for easy integration, but it could also simply be a part of the main board of the TV. They could "hide" the GSM antenna alongside the wifi antenna.
even the ones that aren’t yet, we’d be incredibly incredibly naive to think it’s not on their radar.