Except that iOS and Android are terrible platforms for games. They're all built around the idea of varying resources, having to kill apps when ram is scarce, a call can interrupt any time, and no guaranteed input other than a touchscreen.
For a number of games that simply won't do. Sure you can write games to be underpowered graphically and still be fun, but there's no guarantee someone isn't trying to run your game on a $50 smartphone so you really have to shoot low to get that to work. Also you're competing against a lot of 99¢ or free games in the appstore/market. Sure they're really bad games, but side by side (in the store) the consumer isn't going to know the difference and will choose on price.
I don't want to live in a world with only free-to-play match-three "action-puzzle" games.
Also touchscreen as controls is terrible for any real-time game that doesn't have a one-to-one mapping from what you touch to what happens. (aka, most of them, besides turn-based) I have to be conscious of not only what I want to do, but where the controls are to do it, since I can't feel them.
Nintendo can't build an iOS device for obvious reasons. By the time they strip down android and customise it enough for it to be suitable for gaming it would be easier to make NintendoOS anyway.
Based on the response to Super Mario Run, Fire Emblem Heroes, and Pokemon Go, I'd say their customers clearly do want to play their games on a smartphone; they just haven't had the opportunity.
Now, if you'd said, "their customers don't mind buying Nintendo hardware to play their games on," that's much harder to deny.
Some customers want to play those games. They're not necessarily the same customers. It's not proof they could bring their entire customer base with them.
Those games are made for touch screens. Super Mario Run is proof that no one will ever crack the on-screen joystick problem - Nintendo knew they would not be able to make a good game that way. The end result is certainly fun, but can in no way compete with the experience of a traditional Mario game.
And people will not buy add on controllers for smart phones. Not even for Nintendo.
This reminds me of the arguments a decade ago that Apple should stop making hardware and just license OS X to PC manufacturers. We never would have had good trackpads or mic jacks that can use the clicker on iPhone headphones or all the other bits of integrated hardware and software on Macs.
Nintendo is much like Apple in that they design their hardware features to compliment the games they want to make.
I'm with you. Last console I bought was an XB360. I don't play games as much any more, but anything I do play is a Steam game. I don't have any games on my phone right now, but I do enjoy playing them when I am traveling. I'd love to play a REAL Mario game on my phone with a REAL gamepad.
There's an observable soft spot for Nintendo consoles in a lot of "PC master race" types. I'm definitely not a part of that community, but I agree a higher powered PC plus whatever Nintendo's newest console is brings something very special to the table. It also helps when my little cousins come over and I have games like Overwatch on the PC and Super Mario 3D World on the Wii U for them to enjoy
Almost all features of the Nintendo Switch could have been built on the top of iOS or Android. Nintendo should pivot to a software only company.