While that may be true to a point, I think the Zelda series has a rich enough history and mythos that it could prove that theory wrong that you can have online multiplayerin a story mode that enhances the overall feel and play of the game.
ChatOn has been upgraded to support video chat, and Group Play both allows for sharing songs in a surround mode or playing local multiplayer games -- when it's supported, that is.
You can also expect more warpable bonfires (including some very useful ones) for faster travel later in the game and a new arena mode accessed within the new content itself, making multiplayer PvP much more viable than before.