...Why are we talking about some 5 months thing? It's literally only 3 to 2 and a half months at most? I get it's exaggeration, but it's grossly exaggerating the issue to make it sound worse than it really is.
And the protagonist is still our guess anyway. That, and it has no real story mode, so protagonist is misleading. It's more mascot at this point, which Ribbon Girl is second to him in that regard. Of course people expect the core character. He's the game's Mario. As I said before, this isn't like Chrom where he's just the first of the three main characters the game focuses on. The franchise started with its Mario, Marth. Of course people expect the same to be done with ARMS. It's closer to a Pikachu situation, if you will.
A better point is why even show Spring Man as possible or some of them if these "in-game roles" immediately disconfirm just because of our own fanrules. That goes to show besides the fanrules blatantly being ignored for this kind of teaser, that they wanted to make the whole conversation last longer to get ARMS some attention. That's really are there is to it. It's literally padding. I'm not saying padding is inherently good(though I'll be honest that I rarely hate padding and actually find it fun in most cases) or anything, but that's really what it is. "Why would it be Spring Man?" Why can't it be? He's shown as on the table, so the spirit/AT thing isn't a very valid point anymore.
There's nothing wrong with expecting someone else entirely, even if it's cause of his in-game role(which seems to not matter at this point). But complaining that people are... talking about the Mario of the game getting in often as their prediction seems kind of... pointless overall? It seems just moaning for the sake of it now. Big deal. He's a popular and expected choice. There's always something better to do, like explaining why you don't think it's happening and move on. Or just finding something else to talk about. I agree the conversation has gone on for a pretty long time already, and it wasn't even revealed that long ago. There's little to say anymore of note. We don't know how DLC works for Pass 2 beyond basic details(Character, Music, 8 costumes, Stages, which is it. Spirit Board probably). Isn't Sakurai's column coming out soon? It could shed more light on various things as is. Maybe give us a slight clue.