Observation:
Every single piece of Nintendo hardware since the beginning has not been flatly superior to its competition at the time. Every 3rd party has always dealt with Nintendo's hardware having some notable problems, ironically enough usually in some area of raw performance.
The NES was not as powerful as the Sega Master System in some ways, nor the PC Engine. The SNES was weak compared to the Mega Drive / Genesis in CPU speed. The N64 had nice visual effects compared to the PS1, but often seemed weaker in geometry and games tended to have lower frame rate targets compared to optimized PS1 games. The Gamecube was nice, but GC games often felt geometry starved compared to PS2 games and Xbox 1 games and limited in textures due to the storage medium.
It's kind of a myth that there was a golden age when Nintendo was just awesome as measured by raw hardware power, and 3rd parties loved them, etc. In truth, Nintendo was always the market leader up to a point, combined with past policies trying to control what games 3rd parties released on various platforms.
The Wii was the most extreme version of Nintendo's philosophy, where they entirely avoided competing in the same hardware range as anyone else at the time. No matter what their PR claims with Wii U, the hardware seems to go back in the direction of their old behavior - which still results in something nice in some respects, but apparently weaker in others. A lot of people are still spreading the meme of "Nintendo is overcharging for 7 year old hardware!" including here on GAF, because, you know, stuff like the gamepad is free.
At the end of the day, Nintendo places different priorities than other companies competing in the arena for a certain market of enthusiast gamer dudes. How that philosophy will continue to interact with the current landscape is up for debate.