'reads the first paragraph'
Duuuudes. Seriously. It wasn't that controllers are complex and beyond understanding, people still play Mario Kart with the controller turned sideways. People bought the Wii for different reasons. For instance, WiiFit. I know so many people, all females, who want to lose weight so they look like rakes but don't want to exercise. So they stop eating. Great, now they're thin, ill and tired. So they exercise, but their only concept of exercise meaning anything is going to the gym. But then everyone will see them. So they get WiiFit instead and do pushups.
A Wii isn't considered gaming, so it isn't considered nerdy, so it's considered socially acceptable to play it. People that play console games talk about how boring and wholesome the Wii games are. Only they don't say wholesome, grandparents do, so they give their grandkids this console because it's good for them.
Kay? Not controller complexity like so many people say, other reasons. Lots of reasons. Nothing to do with the controller. Well.. Nothing explicitly, fairly tangential relationship. You should know better.