Lets just say two or more years in future Nintendo wants to bring an upgrade to the Switch, but instead putting the upgrade in the switch itself, they can put it in the dock.
So this new dock will essentially be Nintendo's version of the PS4 Pro, as it will give more power to the Switch, making it capable of 4k gaming and streaming, and similar to the PS4 Pro, there will be no exclusives for it. This dock could also have more storage.
The whole idea for this is that it will make the experince for people who see the switch more of a home console a better experience than ever before.
Discussion started at here by Swoodosaurus_Echx