Nintendo has much bigger problems. They need a better platform and more games and more types of games. They also need better online gaming. I look at it like this. You give a better looking woman more chances and a ugly woman has no chance. Nintendo is looking meh. Unless the price is low I won't touch it. Similar to how a meh woman only has a shot if your drunk and she has the knee pads.
Nintendo needs to get sexy and stop with the just for kids stuff.
Okay, I can give you the better online. But why should they stop the "kids" stuff when those are the kinds of the games they succeed most at, nevermind the fact that their leading three franchises have that appeal (plus some not as, but still fairly popular stuff like Kirby and Donkey Kong)? As long as Mario/Zelda/Pokemon still exist, that will never go away even if they publish more adult games on the side. The only way to get rid of it is to KILL those IP's and even that would cause a s***storm (the loss of three sci-fi IP's, one action-adventure, one racer, and one shooter is bad enough, we don't need anymore controversies).
Besides that, Nintendo appealing to a "hardcore" adult audience almost NEVER worked. The only success was in the N64 era with Rare (and considering the PlayStation's bigger success with that sudience, that isn't saying too much). Everything after that fell hard (although I doubt Eternal Darkness would be successful on PS2 and XBOX, considering Silent Hill and Resident Evil were far more popular) and is why Nintendo has since refused to go that far until Bayonetta 2 was announced (and that in itself is not working for them thanks to what happened the DAY it was announced, which was BEFORE the Wii U even released with all the "underpowered" complaints, needless to say, the controversy over THAT game still goes on). Which pretty much gives me a reason to think much of the "hardcore" adult audience NEVER cared for Nintendo in the slightest outside of one developer that no longer works with them.
Nintendo never wanted these games to work IMO. They also never gave 3rd party games a fair shot either. Hence most of the content seems made for kids.
Yeah, they didn't want the likes of Eternal Darkness, Geist, and Bayonetta 2 to work, that's why they... poured funding into them. Seriously, if they didn't then they wouldn't have bothered to have touched those games.