You understand that the entire purpose of Smash Bros. is to celebrate Nintendo as a whole, right? Not Nintendo's best selling and most popular characters particularly--everything about it. Smash celebrates its mascot characters: Mario, Luigi, Peach, et cetera. Smash celebrates its star franchises: Legend of Zelda, Pokemon, Donkey Kong, et cetera. Smash celebrates its minor franchises: F-Zero, Mother, Fire Emblem, et cetera. Smash celebrates its past and retro works: Ice Climbers, Kid Icarus. Smash celebrates its hardware: Mr. Game & Watch, R.O.B. Smash even celebrates the stars of other companies its had relations with: Sonic, Mega Man.
The whole thing is just a giant celebration. It's not a matter of relevance to our times or sales. This is why you should expect a character like Mii, which has been a huge face for Nintendo as a whole. This is why you should expect yet another retro character to be brought back with a new and intriguing take. Don't count out the small guys, my man. Especially don't try to predict Sakurai.
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