I guess its worth mentioning but is probably obvious but I think it's given a pass because Pokemon is just too dominantly popular for even its own good. Some of the reason that SSB64 did so incredibly well is due, in part, to all of the Pokemon content in the game. At the time, there were really only a select few fighters that the average kid would even know at the time. Mario, Luigi, Yoshi, Pikachu, Jigglypuff and maybe Link. Also, even though it's just another Pokemon, other than Pichu it actually spans a good bit of usable Pokemon in the game. All have unique movesets and don't feel same-y.
For FE, the casual can't help but feel 'so many swordsmen'. To be fair, they really screwed up FE playable representation in Smash. Tried to turn it around with Robin, but all we're left with now is a bunch of lords that use swords even if they work differently. No spears/lances, no bow and arrow, no axes, no shuriken or pure mage. Even FE fans will be the first to agree there.