Yes, we know that you do not understand the difference between a game for everyone and a game for children. You keep hammering that fact home again and again and again. Do we really need to be reminded yet again that you refuse to listen to the reality that Nintendo does not make most of their games aimed at children, and that when I say that they are designed for everyone that it really is true?
Here are some Iwata Asks interviews you should read, so you can learn more about what Nintendo's actual thought processes are behind their games. (Have you heard of Iwata Asks? It's a great interview series.)
Start with some Mario related ones:
http://iwataasks.nintendo.com/interv.../mario25th/0/0
http://iwataasks.nintendo.com/interv...rio_galaxy/0/0
http://iwataasks.nintendo.com/interviews/#/wii/nsmb/0/0
http://iwataasks.nintendo.com/interv.../mariokart/0/0
You'll notice that the emphasis is always on fun, and there is never any mention of the games only being for kids, because they were not. Miyamoto is famous for visiting development teams, both in Nintendo and at external studios working on games for Nintendo, trying the game in progress, and if he dislikes it telling them to go back and try it again, with some tips for what they should do. The goal is to make fun games. Since the Wii particularly Nintendo has also tried to make accessible games that anyone can enjoy, to try to build on their huge success with adults that they had with the Wii; this is touched on in the Mario Galaxy interview above, for instance. This means things like the super-guides to help people stuck in hard levels in some of the platformers (NSMB, DKC Returns, etc.), the Mario Galaxy design decisions mentioned in that interview, etc. The goal is usually to make a game that challenges good gamers, but that a not so good gamer can also play. They usually succeed at this goal. Some games are easier than others, of course-- the Kirby franchise has always been easy -- but even Kirby games have often had challenge, usually from the collection-quest side of things.
As for Rare, games like the Banjo games are supposedly for kids, you might think, but if you compare Banjo to Spyro, you see a huge difference. Spyro is a kids game, covered in cutesey design and with annoying talking everywhere. Banjo... Banjo is loaded with British humor, as you'd expect from a British developer. They always tried, successfully, to sneak through jokes that the supposed "target audience" would not understand, and the game has challenge and complexity enough for anyone who likes 3d platformers. Also, as with Nintendo games, the games are designed to be great games first and foremost. Look at Conker for example, their "mature" 3d platformer, but in mechanics and world design the simplest and most straightforward of their four N64 3d platformers!
Oh, and you completely miss the point with DKR and SSB, of course. Again, the point is that look past the visuals and you'll find two serious, complex, and very challenging to master games.