Let's expand your points:
1. People act like Metroid and Mother (Earthbound) is all about Sunshines and Rainbows when those games are clearly not.
Let's name Snake's appearances on Nintendo platforms:
Nintendo Entertainment System:
Metal Gear
Snake's Revenge
Game Boy Color:
Metal Gear: Ghost Babel
Game Boy Advance:
Boktai 2: Solar Boy Django
GameCube:
Metal Gear Solid: The Twin Snakes (a remake of Metal Gear Solid developed by Silicon Knights)
Metal Gear (Famicom version included in a special bundle of Metal Gear Solid: The Twin Snakes in Japan)
DreamMix TV World Fighters (internal crossover featuring Solid Snake as a playable character)
Wii:
Super Smash Bros. Brawl
Metal Gear (MSX2 version)
Metal Gear 2: Solid Snake (MSX2 version)
3DS:
Metal Gear Solid: Snake Eater 3D
New International Track & Field
Super Smash Bros for 3DS (presumably)
Wii U:
(rumored via Miiverse debug leak) "Metal Gear Solid" V: The Phantom Pain
Super Smash Bros for Wii U
(presumably)
(Yeah Snake is
totally inactive on Nintendo platforms, it's so sad.
)
Metal Gear Solid V could potentially
come to the Wii U where I believe the announcement is held off to presumably keep Snake's return as a surprise.
Megaman has more “history with Nintendo” than Sonic so why wasn’t Megaman included in Brawl? It’s because Sonic was far and away the most popular requested character which shows you how strong of a driving force “history with Nintendo” really is. There has never been any indication that Sakurai chose him for any Nintendo console loyalty or history related reason and saying there is it’s an extrapolation from nothing. Is the criteria about history or is it about current titles? Why does Metal Gear Solid V being on the make Snake more deserving of a spot? Does a new game retroactively give historical significance? Because if this is about new games being on Nintendo platforms, why is fellow Third-Party Mega Man on there? (In case it’s not clear, these are rhetorical questions meant to highlight that the criteria for what is and doesn’t deserve is inconsistent). Snake even has more Metal Gear games and made more Non-Metal Gear appearances on Nintendo platforms than Ice Climbers, Mother (Earthbound) and Kid Icarus. Was Kid Icarus relevant in Nintendo consoles on the Wii? Hell, is Megaman relevant at all right now? The only game Megaman has right now is Super Smash Bros. for Wii /3DS. The Super Smash Bros. series is not about relevance, it’s about icons. Megaman is an icon, people want to see Mega man vs. Mario. Snake is an icon. He’s a character that people want to see him battle against other characters such as Mario, Sonic, Kirby, a Mr. Game & Watch and so on. Examples: Ice Climbers are the icon of the 8 bit Era while Mr. Game & Watch is the icon of the Game & Watch Era. Third-Parties are able to promote the game, broaden the appeal, and increase hype where Nintendo’s own characters are unable to do. As for "How could Nintendo or Kojima could advertise Snake being in Smash Bros. 4 when his game is not on a Nintendo system on twitter?"
No eyebrows were raised when the PlayStation 3's killer app Sony exclusive Metal Gear Solid 4: Guns of the Patriots was promoted in Super Smash Bros. Brawl. You know what else Nintendo did? During the holidays, Nintendo suddenly made an appearance on a random Southwest Airlines flight and gave everyone onboard a free Wii U. In case you were skeptical that Nintendo cares more than just making money.
2. "Nintendoish" what does that even mean? There are many different characters with various degrees of appearances art style personality and so what if the Metal Gear games (with a
few exceptions) is M-Rated? Nintendo is no stranger with M-Rated games such as releasing
First-Party games Eternal Darkness and Geist.
3. Third-Parties are able to promote the game, broaden the appeal, and increase hype where Nintendo’s own characters are unable to do so Sakuari needs all of the promotion of the game Third-Parties could offer.
4. What drove Kojima to "practically beg" Sakurai to get Snake in the game? "My child likes Super Smash Bros., so we play it a lot together. And he told me that there's no character that you made in that game," Hideo Kojima told a group of interviewers late last week ahead of the Smithsonian's "The Art of Videogames" exhibit. Aside from his son's pleading, Kojima pointed to Metal Gear's low profile on Nintendo consoles as a second reason.
"As you know, we did make Twin Snakes, but generally speaking, there hasn't been a lot of Metal Gear on Nintendo platforms. So from that perspective, I thought it was a good way to expose younger people to this character, Snake," he said. What else? Sakurai said the Third-Party characters needs to be "legendary" and being too much of a "PlayStation icon" is exactly one of the reasons why Snake is in Super Smash Bros. Brawl and should push him to make more appearances on Nintendo Consoles to show he is NOT a first-party character who is EXCLUSIVE to PlayStation for he needs to show he is a Konami and gaming icon to the world.
Source:
http://www.joystiq.com/2012/03/19/thank-kojimas-son-for-getting-snake-into-smash-bros-brawl/
Snake is an iconic character and his presence in the game is arguably more of a benefit to Nintendo than Konami. It’s sad that people want to throw out a popular character for reasons like this. People who like Snake will buy Super Smash Bros for Wii U/3DS just to play as him, where people who are not familiar with Snake will look his games up. I don’t see why Snake should be excluded simply because a Metal Game has yet to be announced that it will be released on the Wii U after all you might as well exclude fellow Third-Party Mega Man, Nintendo’s own characters such as Captain Falcon, Samus, Pit, Pokémon characters etc. Metal Gear also has more games on Nintendo platforms than Nintendo’s own Mother (Earthbound) series and has a stronger presence than Ice Climbers and Kid Icarus, Sakuari already made the call that Snake is special enough to be included to the series, the only variable we have to worry about whether Hideo Kojima wants Snake in Super Smash Bros for Wii U /3DS as far as I’m concerned.