This is not a difficult concept to grasp. The original video game crash was indeed caused by, amongst other things, poor quality control. But here's the rub: there was quite literally nothing worthwhile coming out for any system before and during the video game crash. The Wii, on the other hand, has a brand that gamers of all types know to turn to should there be no other offerings: Nintendo. But that's not the case. People here at VG Chartz have utterly overblown the Ubisoft situation so far afield of reality that it amazes me that nobody has called the Ubisoft boycotters on it before this.
As I addressed before, there are very few people who would seriously decide to quit playing on a platform entirely because of games that they never, ever, ever plan to get and have no interest in whatsoever. If the majority of people refused to play a system simply because it had games on it that they didn't like, then the PlayStation 2 would never have taken off at all (nor would any successful console ever have taken off, for that matter). Saying that shovelware can kill a system is shortsighted as all-get-out, if not a borderline ludicrous claim. It's the lack of good software, not the presence of bad software, that kills a platform.
Anyway, Ubisoft is not "killing" the Wii. They're using it and the DS both as a springboard platform to put the budgets into their high-profile games. Just like almost every other development company does. The fact that they're mostly putting out their downmarket games on Wii, and mostly putting their upmarket games on 360 and PS3, is just a form of demographic identification. They're not even that far off in their assessment, either; not one hardcore game has done anywhere near as well as the downmarket games like Wii Fit have on the Wii, save the ones made by Nintendo. And like most companies, Ubisoft doesn't understand why, so they go with the easiest formula: put the downmarket stuff on Wii (where they know it'll sell), and put the upmarket stuff on 360 and PS3 (where they know it'll sell).