Looks like this one's being interpreted in several different ways based on what each person reading already believed. Some are using it as "proof" that Byleth was nothing more than a shill pick. I read it as Sakurai saying "no, my personal bias didn't influence who we chose, we have a decision process" because that's what I've been trying to point out myself.
And apparently the translations we have so far were rushed, so we don't actually know if they're worded properly yet.
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Not really Push's fault, though. Apparently the reason why he rushed out a quick take of the part that leaked ahead of time is because a
different translator jumped the gun first with a shakier version.
For what it's worth, he himself thinks it was referencing accusations of "Sakurai bias", not why Byleth was chosen in particular.
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Not that it's prevented some news groups from reacting to the first translation and jumping to conclusions, because
goddamnit.
This is going to be a mess, I can already tell...
Right now? Some kind of statement from Sakurai that outright says spirits are ineligible, I suppose.
Well, it might be a bit more complicated than that. Back during Smash 4's DLC, development on Corrin seems to not have started until some time between April and June of 2015, as Corrin's placeholder data didn't show up in the game files until the update in June. Given the circumstances, it seems like they set aside a placeholder for "first party character from a relevant title", then waited several months until the spring before deciding who within that niche to choose. Given Byleth's similar circumstances, it's plausible that they did the same thing for Season 1 of Ultimate's DLC. If this theory is true, then Byleth was
not chosen before the base game was out, and wasn't for another several months.
And either way, the accompanying spirits wouldn't have been set up until
at least around when development on Byleth began.
But what this
does mean is they had no problem with going back and updating older spirits' names after the fact when a new situation came up. And since there's a pretty fair chance the SwSh spirit event was a Season 1 creation, Season 2 is another new situation.
Well, at the very least, now they could differentiate by using "Zacian (Pokémon)" and "Zacian (Fighter)", for example.