To me. I think that Nintendo is still very much "mainstream" in the gaming audience, both casual and dedicated. Anybody who has every picked up and played a video game knows who Mario is and what Pokemon are. Wii U aside, the 3DS is still doing great. Their top selling franchises are still doing outstanding. Mario Kart 8 has a legitimate shot at 8, maybe even 9 million copies sold worldwide. Which is ABSOLUTELY AMAZING given the circumstances surrounding it and everything that it has had going against it.
So amongst gamers, they are still very much mainstream. Always have been, and as long as they continue to make video games, always will be.
Outside of gaming however is where they are NOT mainstream.
See, when something has mainstream appeal or knowledge, it doesn't necessarily mean it is well known or caters to one form of entertainment media or one population, in this case, video games. But is well known or caters to EVERY form of entertainment media and EVERY population. It is thought about, taken into account, and well known by everyone. It's cultural.
Disney is mainstream. Sony is mainstream. Microsoft is mainstream.
Nintendo, while having being recognized and respected by all gamers, are not as mainstream or as recognizable to the rest of the world as the other 3 companies I just mentioned. People may know who Mario is or what's a Pokemon, but not Nintendo specifically.
Disney, Sony, and Microsoft are mainstream because they are active, involved, have products, and do things that are recognizable by so many different people across the globe with different tastes and preferences, not just gaming.
Disney isn't just about making cartoons, they do movies, both live action and animated. They do TV Shows and sitcoms, documentaries, they have amusement parks. They own 32% of Hulu so they're involved in streaming. They also make video games, with Epic Mickey, Disney Infinity, and Kingdom Hearts. They're involved, established, and influential in many sides of the entertainment spectrum, not just one.
Sony is involved with making movies, they make TVs, they have their own music divsion, which has had some of the most popular music artists EVER, (Bowie, Dylan, Beyonce, Mariah, Paul, Michael), you could make a very strong case for their PlayStation brand being their most popular one and even a stronger one for their most successful. But they're involved in many different areas, they may not being doing so good in many of them right now, but they're involved.
And Microsoft, oh boy Microsoft. Anybody who owns a computer, laptop, tablet, or any electronic devices knows about Windows, they have Office, Skype, they essentially dominate the computer industry. They practically invented the Internet, or at least made it into the huuuuuge deal that it is today. Plus they have the Xbox brand too, which is also pretty popular.
All of these companies have all of these different divisions, and are involved in so many different things. They have evolved, grown, and expanded to the point where you can't walk 2 feet without seeing or hearing something that came from them.
I don't think the same can be said right now for Nintendo. It can be said for Mario and Pokemon, but not Nintendo.
The difference between Nintendo and the other 3 companies I mentioned is this:
If those 3 companies lose money on their gaming divisions, they have so many other divisions to keep them afloat, or thriving in Microsoft's case, to where they can continue to have widespread appeal, mainstream popularity, and not miss a beat.
When Nintendo loses money on their gaming division, it is a very serious deal, because that's their bread and butter, their only division, so they can't have as much appeal or take as many steps and do as many things as the others do to be mainstream, because first they have to try to profit off of where they are right now. That's the biggest reason why their consoles aren't always up to snuff and they cut corners and don't release at the same time or at the same level as Sony and Microsoft, because Sony and Microsoft can afford to take losses on their gaming systems having all of these cutting edge specs and hardware in order to have the highest install base, the largest spread, and biggest appeal all over the world. Nintendo can't... and Nintendo knows this.
That's why they are venturing into all of these different branches with mobile games, amusement parks, TV, movies, anime/animation, Quality of Life, etc. So that they can widen their reach. So that they won't be just a video game company anymore. So they can grow to the point where they, as a company themselves, will be more recognizable by people across the world than their own mascot. With the success of the Wii, DS, and 3DS, Nintendo is in a position, financially, where they CAN become mainstream just like the other 3 I mentioned, Disney in particular.
The reason I say Mario is mainstream and Nintendo is not, is because Nintendo relies so heavily on their mascot to drive sales and bring in profits to the point where Mario is all people know and because they see him so much and Nintendo puts so much effort and money into him, that's all nongamers are satisfied with. It is definitely good for the Mario brand, but not for the Nintendo brand overall, how many of our parents, grandparents, or family relatives or anybody we know who has never played or cared about video games know about Zelda or Metroid for example?
Meanwhile look at Disney, and I'm sure anybody on the street can tell you 10 different things from Disney right off the bat, whether it's from movies, TV, amusement parks, video games, etc. You mention say, Cars, Frozen, Lion King, Winnie the Pooh, or Big Hero 6, or Cinderella, Disney Infinity, Epic Mickey, and people will immediately say, "Oh yeah that's from Disney." In fact, I'd even say that Mickey, while easily and clearly the face of Disney, is not as immediately recognizable today as the company as a whole by itself. Disney is at the point where they don't need Mickey to do much in order to be recognizable across the globe by so many people becaue they're involved in so many things. Hell, I'll even say they could drop Mickey entirely and they'd be just fine.
That's where Nintendo is trying to go with all the things they're getting involved with now. To be mainstream with every audience in every spectrum of entertainment they are in. To be recognized across the globe by hundreds of millions of people with different tastes, styles, ways of life, and preferences of entertainment the way Sony, Microsoft, and Disney are.
And I'll throw this last bit in for extra credit:
If Nintendo DOES get to that point where they're THAT successful and THAT big as a company where they don't have to rely on their dedicated video game hardware and software business NEARLY as much as they are right now. THEN they spend more money, and be more advanced and up to snuff with their hardware, because they won't have to worry about losing money off of it because they're making so much more money off of everything else, they can go on without missing a beat. And if they're at that point where their system is on the same level and released at the same time as the other 2 systems, they'll be getting all of the 3rd party games that they're sourly missing.
A Nintendo console that is up to speed + all 3rd party games + their exclusives = Oh My Goodness, what an Amazing System!!!
If Nintendo can manage to do all of that, it will be tough, and it will take a lot of time, money, resources, and dedication on their part, but if they can do it, while still remembering their core values and beliefs as a company and why they're so respected by gamers, then yes. They will absolutely be mainstream again.
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