Er... people difficult games died with the SNES. Supposed "hardcore" gamers nowadays have no idea what a difficult game is anymore. That said, Mario Strikers Charged is the most difficult game I have played since Ninja Gaiden on the NES. That game kicked my ass all over at the higher levels (and I haven't found a game able to do that in years). Meanwhile, I could beat God of War blindfolded while holding the controller with my feet.
But seriously, come on people, stop twisting statements to fit your purposes. What Miyamoto is trying to do is simplify controls to make games accessible. He's criticizing games that use control schemes so complex that it drives away all but the most determined gamers. What he wants are games that are fun and easy to pick up. Strikers has very simple controls, but I'd like to see one person on this forum who has beaten the single player alone (you can play it with a friend, and if you are both good, the insane AI is much more manageable).
The point is, truly hard games are rare in the current market (most shooters are a joke). Games have been getting easier and easier for years, and Nintendo's goal isn't to speed up this process, but rather make games accessible. Difficulty shouldn't be a barrier in playing the games and enjoying them.
Think of the best and most popular games of all time. We have what? Super Mario 64, Gran Turismo, Ocarina of Time, Final Fantasy VII, Pokemon, Grand Theft Auto, the Super Mario Bros. games... none of those games are difficult. Sure you can go for higher level stuff in Gran Turismo, but anyone can pick it up and play it. Ocarina of Time was a very easy game by any standards, but is widely considered (and reviewed) the greatest game of all time. Final Fantasy VII is without a doubt the easiest Final Fantasy game I have ever played. Metroid Prime's first play through is easy, and it's the 3rd highest rated game of all time. You unlock a more difficult mode after beating it the first time (something I am sure will continue with MP3). Grand Theft Auto 3 (and it's sequels) were some of the easiest games I have ever played. Pokemon is only difficult if you get into tourney gaming online.
Miyamoto's point is simply that it's stupid to make a game which is so difficult to play that it's limited to tiny groups of people. History shows that this is in fact the case. Easy, or at least accessible, games are always the most popular, the best rated, and the highest selling. When I want a challenging game, I hop on Starcraft or Counter Strike and play online. Or I grab my copy of Pokemon Pearl and enter an online tourney (if you people really want to see how insane video game strategies can get, check out a Pokemon Tourney). AIs rarely challenge skilled gamers, but even the ones that do are not necessarily better than games that don't. What was your favorite game last generation? Somehow I doubt it was difficult...
There are many ways to make a game fun. Making it difficult is only one, and there are certainly other ways to find difficulty in games than single player experiences (and there are difficult single-player experiences on the Wii too). Nintendo has spent the last 10 years trying to make games accessible, and I applaud them for it. Nothing has changed in their strategy, they have simply gotten much better at what they have been trying to do for years.
/end rant. Sorry it was so long.