Technically true, but unlike the other three, Excitebiker isn't
solely representive of the days of the past.
All
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had was Gyromite and Stack-Up.
All
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had was Duck Hunt. And Wild Gunman and Hogan's Alley if you want to go by how they represent those games as well in Smash.
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had the Game & Watch line of handhelds from 1980 to 1991. Sure, there were the Mario-themed remakes from 1997-1999 prior to Melee, but those are just remakes.
Excitebiker has the original title, Excitebike 64, and the WiiWare title. And the Excite series in general
also has the two Wii games, Excitetruck and ExciteBots.
This is an impossible claim at this point in time. Excitebiker literally cannot be considered part of this "niche" until
after the fact.
Besides, the only latent "surprise" about Excitebiker being playable would be the fact he was outright
rejected in the past (which in itself is still would not be much of a surprise because Villager broke that barrier already) and because he was initially an Assist instead of playable in the past as well (which Charizard and Little Mac had already broken the barrier for).
It would not work to the same degree as the other three, who were
not discussed about previous consideration before their Smash debuts nor had roles in a previous Smash prior to their Smash debuts.
No arguments there.
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didn't have successful games.
He may have kept video games alive in the West during the Crash of '83 long enough for Mario to usher in the new era of gaming, but Gyromite and Stack-Up did
not sell well.
NOTE: I have absolutely
no problem with Excitebiker being in Smash if it's actually possible within reason.
I just have issue with the logic that he'd be within the same "niche" as G&W, R.O.B., and Duck Hunt when someone like Star Man would be closer to the "niche".