Nintendo and Third Party... Who is really to blame?

[Soundwave]

3rd parties are not entitled to make games for anyone. They weren't entitled to support the Sega Master System or Turbo Grafx 16 or 3DO or Atari Jaguar or Sega Saturn or Sega Dreamcast or Sony Vita or Wii U.

The truth is Nintendo lost the "Nintendo gamer" who would buy a more balanced staple of games, including sports games, third party titles etc. Those were popular on the NES and SNES, but they alienated this audience with the N64 and never won it back with the GameCube. 

As a result what was left for Nintendo was a more narrow hardcore Nintendo fan that preferred Nintendo franchises heavily. 

Gone were the people who loved Megaman and Contra and Ninja Turtles and Street Fighter II and Final Fantasy as much as or even more than Nintendo's own IP. They left to Playstation or XBox. 

The Wii really didn't rectify this issue either, even for all the early success it had, it was mostly from fickle casual gamers who just wanted things like Guitar Hero or Carnival Games, it didn't help the studio wanting to make other styles of games. 

Nintendo's policies made them lose a large chunk of their audience to Sony and MS.