I don't see anything in the first post that indicates you were joking.
However, the picture in question is intentionally deceiving: I'm guessing it's a picture of Pit and Link each charging smash attacks (indicated by the sparks on each of their weapons) but Sora has placed them in such a way that it looks as though they're engaged in an epic sword battle.
They did a lot of this with Melee, making the fights seem more "epic" than they truly are.
And by the way, stick with your theory, don't try to pass it off as a joke because people are being antagonistic towards it. You had the guts to speculate and that still makes you better than the people who ridicule you for it.
Besides, when I first looked at the screenshot, I thought it might have been a new means of blocking as well, but I think the truth is, the bubble will stay not because it's tradition but because the bubble is the most "casual friendly" blocking system and we all know how big Nintendo is on making everything more casual friendly right now.