You're using the definition of "peripheral" as it relates to PCs. In console gaming, we use the word "peripheral" to differentiate between a controller that comes with the console, and a bonus controller that is only used for a few games.
The Wii remote and nunchuck are the main controller.
The Wii peripherals are the Balance Board, the Wii Wheel, the Wii Zapper, the Classic Controller, Wii Motion +, DDR dance pads, maracas, GH/RB guitars, drums, and microphones, and the Active Life power pad.
And most of those are peripherals in the sense that they actually have to be attached to the Wii remote itself.
Yes, any other input could have been used in an alternate history, but that doesn't matter. A TV can be used without a remote. A Wii can't. Nothing can be done on the Wii whatsoever without the remote that comes in the box.












