Nintendo already has Mario, Zelda, Metroid, Pokemon, Kirby, Star Fox, Pikmin, Fire Emblem, Animal Crossing, Kid Icarus, and Donkey Kong as distinct major franchises. For more minor franchises they have Mother, Golden Sun, Punch-Out, the Wars series, and F-Zero.
And then they've got a long list of other one-off or two-off properties like Custom Robo, Dillon's Rolling Western, Rusty's Real Deal Baseball, Elite Beat Agents, and probably a bunch more. And now there's Splatoon.
I mean, I think they've got more major and minor IPs than any other single developer or publisher out there. They can barely juggle all these and satisfy fans with periodic releases for most of them.
Why exactly are people scrambling to get more from them? They're one company; they only have so many people making games. You start tossing in a brand new IP every year or two and more updates to other, less used franchises, and suddenly you're waiting 10 years between Zelda games (we're already waiting something like 6-7), 8 years between Mario titles (already 3-4), etc.
We could use a little more balance between everything else and Mario, maybe, but Nintendo comes up with plenty of new IP like Splatoon.
