The Wii U could be better but it's still the most powerful console on the planet so yeah.
I should note I may be arguing a different definition of "low tech" and hence any possible confusion.
The point is that neither of those were using the latest and mightest tech available at the time, allowing competitors to provide far better hardware in a short timespan.
It's different from the 360 and PS3 situation, for example: the PS3 got released one year later and the 360 could still keep toes with it. This is the definition of "high tech" people are talking about.
Actually Nintendo has not changed that much over the last 30 years.
The focus was always to build an affordable machine for their own software with sufficient hardware power to support Nintendos own vision for gaming. Connect people in front of the tv etc etc. The N64 was the only kinda exception to this rule having a hardware way ahead of it´s time. The cube was again a well designed machine within the limitations of the tech of it´s time.
But at the same time something changed. Iwata and Yamauchi both understood one importand thing: As stated above, Nintendo always build hardware to support their own vision for gaming - but with the introduction of the cube, graphics had reached a level of fidelity which was, for nintendo, decent enough to support their visions. Any better graphics wouldn´t add anything to the gameplay itself. Considering this, the Wii was just the natural way to go for Nintendo. Envision new ways to play and build the hardware for it. There was never such thing as a "change of mind" or something similar.. Iwata himself explained all this at the E3 in 2001:
http://www.youtube.com/watch?v=jWSmFjOgyG4&feature=mfu_in_order&list=UL
@8:40min
I agree. The N64 was the only instance where they aimed too high. Even then, some decisions were made based to server Nintendo's own needs: the controller and using carts instead of CDs.
The NES, the SNES and the GC were mostly made with what was available and affordable at the time. Heck, the NES and SNES were actually incredibly weak and technical evolution was only possible through extra chips added to the cartridges.