I'm not sure I agree with you. The NES and SNES systems were hot sellers and they had a lot of good titles mixed with tons of mediocre ones. I think that in terms of games, the Wii is walking the same path of the Gamecube - with a major difference: the Wii is a continuous best seller and attracts third party developers.
I couldn't agree more with you when you mention pop music, but the more popular a console is, the more chances it has of having great games - after all everyone will want to program games for it. Playstation 2 is also a example: a lot of rubbish and casual titles and a lot of great games (I would kill to see Shadow of Colossus on the Wii). There is a big problem happening, though: developers are beginning to realize that the Wii can't keep up with graphical inovations and are giving up on the console or developing casual games for it. I'm not a graphics obsessed gamer, by far, but I understand that nowadays if you want to sell a game based on its visual impact, you will have to do it for the 360/PS3.
Anyway, great ideas don't need great technology, and the time and cost of working for a PS3 game is amazingly higher – and we could see some developers shifting to the Wii.
I have no interest in Mario Kart, though. Not a big fan of driving games.
All this talk should not distract us from the main subject: the Wii has plenty of great non-casual games waiting for you to play them.
I agree with you on Zelda (the game was just too long and rehashed), but by not including it people would think that I was just looking for controversy. :p