The way I see it, deconfirms work like this to me:
1. Sakurai outright tells us a character won't be playable in this version.
(I know some people exclude characters cause of exclusion in older versions but ... villager, sakurai re-evaluates what he expects from fighters each time.)
2. The character's most common/only/most iconic form is somehow present during regular play.
ROB didn't qualify cause common subspace enemies don't actually show up in regular play.
Toon Link's train form didn't qualify because, as some people pointed out, he's not particularly easy to mix up with playable T.Link (alt colours or regular)
When I see a character as another characters move though, That essentially turns them into someone as ingrained in popular play as an assist trophy. It'd essentially feel like having charizard *both* playable and as a pokeball pokemon. ( a big reason I'd say Toad's chances are essentially zero.)
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