I understand it would be cool if nintendo had more mature content for Mario to do. You know, flesh out the guy some more. Make him relatable.
But for Nintendo to go more goreish isn't really the way. FPS, been done, way done. Fighting game with blood splatter. How cool is that really after so many titles blasting digital blood. That's not the way to mature Nintendos image.
I can even argue that Nintendo is far more mature than the other consoles. I say provacative titles like "brain age" matured Nintendo.
As for Gears of war, Drakes fortune, God of War, Halo, killzone; all considered to be for mature games. But really, who are they targeting? I'll coin this phrase, "Arnold Stallone Action Shit"(ASAS). ASAS--Where the broad appeal of something is how action oriented it is, or heavily impacted by alpha male attitudes. For instance, the Expendables 2, is some ASAS.
Those games were fun, but mature as those are, they are also immature. I'm looking at you Kratos and you many sex scenes.
Sure, Nintendo gets colorful and vibrant on their games, but that's not kiddy, that artistic vision. Look at Conkers bad fur day. It may look kiddy, but the attitude is all adult.