We can't base this off of 1 console generation, that's flawed logic. Wii sold because of the widespread gimmick. And of course, their 1st party content was amazing but coming off the Gamecube, we can't assume that everyone bought a Wii because they wanted more 1st party content. It was the hype surrounding the Wii and the breaking of the general idea of what a gamer can be. Nobody bought the WIi for multiplats because the multiplats were half assed and the Wii lacked the robust online features that PS3 and 360 had, it also lacked the graphical capability that those consoles had. Nintendo had a good relationship with 3rd parties but the neglect that third parties have recieved with Wii and Wii U, has formed a bond with PS and XB that even if Nintendo had the right hardware for 3rd parties to flourish, they wouldn't be comfortable putting their content on a Nintendo console.
We look at the software sold on the Wii and it speaks for itself.