Here's how I think it went down, and yes I am guessing, but also using my common sense.
I agree that the original teaser was just that, and nothing more. However, I think Konami did plan to make a next gen at the time, it probably would not have look like that but they wouldn't have been the first developers to downgrade something from an initial teaser. However, at some point the project just became too big in their eyes, and someone says (and yes I am reaaaally guessing now) "Damn, if only we could make this as easily as the mobile game, that thing is making us the real yen here" and in that moment, a lightbulb goes up over everyone's head. Ditch the real next gen project, base the whole thing on the mobile version, make some half-decent intro sequences and cut-scenes so they can act like it was next gen all along, have Adam and co drum up some spiel about waiting to play before judging, and if people are unhappy, so what, we are getting our money.
The reason why I think this is that this game LOOKS LIKE ASS. And not playboy model ass, but plumber ass. I played the "New Football Game" beta and it was absolutely HIDEOUS. Then there is the myriad of other sub-par things we have all seen in gameplay videos, things cut, simplified controls, skating all over the place, if it took them two years to port their (already existing) mobile game to consoles, they must have some seriously short work days. I just can't buy it.
I would like to add that I am not trying to defend Konami here. I don't think this is any less shitty than if they never intended to do anything but a mobile port to begin with.