Why would I play offensively when I can just have you approach me and my fan+electricpad+guard? That's good setup for me to do my other AP gaining attacks. A lot of characters in this game have no offensive/pressuring moves outside of Raiden, Kratos, Nariko and Sly. So they resort to camping and throwing whatever bananas, mines, bullets, barrels, cake, fireballs, thunderballs they have to get the upperhand. This nerf just means that Sackboy is going to have to camp harder and longer to get his Supers, it's not going to change the way people play him at all.
Though the nerf will kick him out of the supercool omgwtf hack & slash tier, otherwise known as top or god of war tier.