A lot of these claims are surface-level accusations, often without any consistent data to back them up. If it were truly the cause of their downfall, it would have gotten them the first time they used such tactics. To wit:
* Mistreated 3rd parties - They did this with the NES and SNES too
* Used cartridge/proprietary media format - They did this with the NES and SNES too
* Anti-piracy measures - They did this with the NES and SNES too
* Family-friendly image - They did this with the NES and Wii too
* Lack of video-playing format - They have never supported video play-back
* Use of strange controller design - They did this with the NES and Wii too
* Game prices too high - They did this with the SNES too
* Used outdated technology - Every system Nintendo has ever made has been with outdated technology
* Were too greedy - Their greed levels have never changed
* Used odd colors - The Game Boy Color's initial model was also purple
As none of these shortcomings have led to consistent downfall, and particularly since every single characteristic was present BEFORE their downfall, that means they are not the cause of the downfall; they are merely agents of their fall (for some of those, anyway; I think the arguments of casing color and video playback are particularly ridiculous) which became disadvantages. But advantages do not become disadvantages in a vacuum; variables must change for that to happen. That being the case, the true cause lies outside of the perceived shortcomings, in the change to the market which made those characteristics into drawbacks.
I've already covered the actual cause above: their shift in the market from being the pioneer of a highly-monopolistic blue ocean product to a competitor in the vicious red ocean of non-differentiated products where the player who brings the most financial clout to bear in the most effective manner wins. The traits people list are largely advantages in a blue ocean (or irrelevant characteristics), and a good deal of them become liabilities only when your fellow competitors have products targeting the same consumer values as yours is.
Sky Render - Sanity is for the weak.
