Is there? Kids game on phones and parents dont game much if at all. And when they do, on their phone.
We are all phone zombies now.
Well, think of it this way. 3DS has sold 60 m LTD and Wii U 12 m LTD.
I'm sure there's an overlap of 3DS and Wii U owners and many individuals will have bought more than one 3DS iteration but there is a sizeable market for Nintendo, casual, party, fitness, dance, sports games in the tens of millions.
Those Pokemon, Mario 2D, 3D, Kart, Party, Golf, Tennis, Donkey Kong, Starfox gamers aren't just going to vanish.
If Nintendo can get a console out at a mass market price (say, minus optical drive and hard disk to keep price down), the market will respond. Where else can they get Nintendo and quality, curated casual games on a dedicated console with a proven, family safe reputation?