Yeah, lets just completely ignore the fact that most of Nintendos games are completely build around the specific hardware they were released on and are more creative and unique for it.
Whatever controlscheme Nintendo comes up with, they usually commit to it 100% (the WiiU being the outlier here, they really didn't know what to do with that system....). Hundreds of games would have been impossible without Nintendo RnD developing their own hardware.
People tend to forget how revolutionary a lot of Nintendo hardware was for it's respective time and complain about gimmicks instead.
I'll tell you what, the DS, had a touchscreen in 2004, thats three years before the Iphone released and made touchscreens ubuquitus. And it did give us new ways to play. I could go on, but it's save to say, demanding Nintendo to go third party isn't thinking things through.