Let me try to clarify this for you, to accomodate the apparent conflation of disparate points. I apologize if I came off as agressive, but it's frustrating to exchange forum posts, in lieu of having an actual, human conversation.

Since 2000, all but 2 of the top-selling video game has been third-party, multiplatform. Consequently, for the last ten years, gaming has trended away from first-party gaming. Since 2008, the top-selling video game has been third-party, multiplatform. From 1984 to 2000, however, every top-selling video game was a first-party exclusive. The games that broke the first-party trend, from 2001 to 2006, were the usual fare: GTA, CoD, and Madden. In 2007 and 2008, the best-selling games were Halo and Wii Play, respectively.

I think this is where the confusion arose. There's a clear trend towards third-party, multiplatform games driving the industry, and it extends long past their last decade streak. Despite that, the Wii (which was a massive success) saw almost exclusively first-party best-sellers (the aforementioned top 1-17). Some argue that third-party disdain for Nintendo started with the N64 and its cartridge format, but I remember there always being an N64 version of the big titles. The Wii's success was predicated on its mainstream appeal as the novel, accessible, essentially easy-the-play console. The only system my non-gamer sister has ever owned was a Wii, and she is the rule, not the exception. It was unique, accessible, and favorably priced, and the market responded accordingly. If you look at the top-selling games list, Wii Sports, Wii Play, and Wii Fit take 5 of the top 7 spots. I bring that up to note that this system was not carried by games for the traditional gaming audience, but rather for the casual audience. It's first-party success was, in essence, wholly aberrant, because those games were built around the system's novelty. This is why the lack of third-party success and support is important context and why the first-party success isn't very meaningful, in the face of current gaming ecosystem.

The Nintendo Switch is built around the traditional gaming audience, which has trended towards the third-party best-sellers that have trended away from Nintendo. It's not surprising, given the sales figures that we've gone over. The Switch, much like the Wii, has to rely on its novelty to be successful. Nintendo has made it clear with the launch price, specifications, etc. It seems unlikely to me and is my greatest concern that the casual gamer that bought the Wii is not interested in the pseudo-novelty of a portable system. Seeing as we live in the CoD, GTA era, I would fully expect the traditional, mainstream (hard term to use, because the Wii was a truly mainsteam system) to look for the best versions of those games. Then, Nintendo gets caught in-between.

I don't really care if they're immature or not, I just liked having tonal variety. It was nice to break up the colourful cartoon sweets with a bit of spicy horror or a savoury shooter. I wouldn't be interested in the Switch if it's only going to offer me a monotone library.

I think its a bit of an oversimplification to say that the Wii sold only because of it's motion controls.

Some of its biggest sellers, like New Super Mario Bros Wii (28 million) and Smash Bros Brawl, (13 million) use them barely or not at all.

The Wii had more going for it than just motion controls; it was significantly cheaper than the competition, and in addition to blue ocean titles like Wii Sports/Fit, it provided highly desirable "core" games like the dark Ocarina successor Zelda fans had been waiting for since the N64, an epic 3D Mario widely considered one of the best games ever made, the first 2D Mario on a home console since the SNES, etc.

Success in this industry snowballs. So when things go good ... things go *really* good in this business. 

The Wii U had NSMBU and Smash Bros. and Mario Kart and Wii Fit/Party/Sports even as well. And it was cheaper than a PS4 or XB1 as well. 

That sold like shit. 

Wii is just an outlier to be honest. There's never been a console that had the metoric rise it did, followed by the equally fast meteroic crash that it had. It's a unique situation, there never will be a Wii again most likely. 

The market in 2006-2010 was vastly different to the market of 2012 onwards. You can't expect the same strategy to pay off in totally different market situations, that's like expecting a boat to work just as well on land as in the water. Wii was a good read of the market of the mid 2000s, Wii U was a very poor read of the market of the early to mid 2010s.

Yeah it'll never happen again. Even just for novelty people had been using phyiscal buttons for like 30 years, so the initial senstation of using movement for control was completely mind blowing and went againt 30 years of established "rules". 

But today? Meh. Sony has motion controllers. Your phone has motion controllers. The Xbox had a motion camera. Tablets have motion sensors. The Apple TV has motion controls. I think there was a push for a little while for TV remotes to have motion before as well but most manufacturers have kinda backed away from that and just gone back to regular old buttons on remotes. 

I didn't say the Wii explosion would happen again. I just don't think we can assign all the credit for its success to motion controls when we consider the other factors in its favour, like being considerably cheaper than the competition, having highly desirable games like the successor to Ocarina of Time and the return of 2D Mario to home consoles after an 18 year absence, etc.

Yeah 10 years is just ridiculous. I mean, there's a reason 5 years became the standard and it's because people start to get tired of the same old thing and want something new around that time. 

I just made this point on the Wii: it truly was an aberration.

Agreed. I got bored of Wii/PS3/360 in 2011.