There's a reason it doesn't apply for every character. But for some, yeah, it does. Ice Climbers is literally a pure case of "we saw a unique gameplay potential". They were not honestly memorable. Also, it's not like the whole idea is solely looking at the Famicom era here. Honestly, that wasn't even the point being made. Just that taking a non-memorable character and putting them in Smash is a great way to make them more well known. That was the point they were clearly making, and they're right. A lot of obscure characters get heavily known due to Smash, even when it comes to simply being nothing more than cameos/trophies. Smash is the best way to streamline characters to the world. Even Japanese characters. Lucas, Roy, Marth, they were extremely obscure in the US, and not really notorious there at all.
That said, I did miss some context, but I disagree with the idea that a game can't have a character worth adding just because they're obscure. That just feels like ignoring a potential option for the sake of it. If they can't make them work and be interesting, then they're not worth it. Obviously there may be better options at the time, due to things like moveset, what would appeal better, easier licensing issues, etc. But I'd say Lark is a perfect example of someone who would be great to add, if they can create a good moveset. Pilotwings is actually not that obscure of a franchise either(and frankly, Lark is just as memorable as Ice Climbers, that is, not at all, which is what undermines the entire comparison trying to be made beforehand. They're both exact examples of the same situation. The only difference is Pilotwings was an actual popular game. Otherwise, no real difference beyond moveset potential being seen, and that's questionable).
