Why Nintendo doesn't release a second screen adapter?

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Nintendo Switch - News, Updates, and Information

I've seen that the solution that a lot of people propose to DS or Wii U games on the switch is to attach a second screen to the switch or something similar. but Isn't it possible to release a device that connects the undocked switch to the dock via wifi/bluetooth or whatever so the switch transmits the game info to the tv while separated from the dock? I think the major problem would possibly be latency but they also could add a very long cable that connects to the adapter In case anyone wants t