The Xbox is doing it that way because they need the lowest input latency possible for the controllers. Blocking the antenna for network operations delays the user input. A TV doesn't have that problem and certainly won't have two antennas.
We are effectively helpless against those tinier and tinier SoCs and the only option is not to buy.
Smartphones typically have four (or more) antennas. 2 for cell (main and diversity), one for wifi/bluetooth, one for GPS. Some phones compress that down to 2, but lose signal strength by doing so.