No, thats like thinking only Liu Kang can represent Mortal Kombat, Sakurai flat out stated his reasoning, gave plenty of it, and even then fans were already predicting other characters for a variety of reasons, none of it related to the AT issue. If people STILL want to pretend all of it doesnt count just to say theres a rule and thats why their "prediction" was wrong or that the character got robbed simly because you predicted etc.. (no really you cant just go "all this evidence saying otherwise doesnt count because I dont want to and I wanted to predict otherwise even though I have no sourcing: this is what flat-earthers do").
then its time to accept this is denial and move on. Springman is NO Ryu and never will be, he had one game, tons of fighting games have the villain or a someone who started as a side character being considered the face or being used in all of its crossovers, its nothing new, even amongst Heavy Hitters, the "Ryus" are pretty rare actually.
At best Springo can be an important character later on depending on what a sequel does but he ain't no Scorpion, no Morrigan, no Nightmare, no Heihachi etc, now you can give a technicality as to why these examples were actually the traditional protagonists all along because of this or that, but the same goes for Springo and Minmin, make an Arms 2 with the whole cast in the cover or with a new guy, or with Min Min and this discussion is done. Its time that people accept their preditction just happened to be wrong, he wasnt going to make it and that it doesnt interfere at all with any other AT getting in, because even if Sakurai is against it, this STILL has nothing to do with the ARMs choice as it didnt even get to that point, Sakurai was flat out considering the two finalists of the big tourney even.