Miyamoto explains the shift away from casuals.

[NightDragon83]

Clyde32 said:

NightDragon83 said:
Nintendo didn't leave the casuals, the casuals left Nintendo when they realized they can pay a couple bucks a pop for their entertainment on their smartphones rather than $250-$300 on a console and $50-$60 a pop for maybe one or two games a year.

Wait..what?

Ever notice how the Wii sharply declined at the same point that tablets and touch-screen smartphones became mainstream?

That's why the casuals left Nintendo.