Well ur basing that off of pretty much nothing, Nintendo made a console that doesn't appeal to casuals this generation, that however doesn't mean casuals are no longer willing to buy consoles.
To say the Wii U isn't aimed at casuals I think is a bit of a lark. It's branded the Wii. A casual brand. All the TV marketing was for the casual/family demographic. Half of Nintendo's first year titles were party/mini-games. The lead title for the system was Nintendo Land, a game aimed specifically at casuals. It uses a toucscreen controller similar to other popular casual gaming devices like the DS and iPad.
To say this system was aimed at hardcore players is a laugh. The PLAYSTATION 4 is aimed at, marketed to, and built for core gamers.
Wii U was aimed largely at casuals with a few concessions thrown in to hardcore players (here's clickable analog sticks and a port of a crappy Ninja Gaiden game and the same Call of Duty you can already play on the your PS3/XBox!).
Nintendo just failed this time out because that's the nature of the "gimmick controller" beast ... sometimes it hits, but the Wii U showed the dark side of that approach ... if your controller idea doesn't take off, then you're basically screwed. It's not even like they divorced the Wiimote from the Wii U. You can't even play the pack-in title (Nintendo Land) without Wiimotes, as the game basically requires Wiimotes for any kind of multiplayer. The system was clearly designed to be sold to the existing Wii audience. Heck in Japan the Wiimote still comes bundled with the Wii U, yet this is the lowest selling market for the system.