Well if they had a platforming system in, then by all means acrobatics should be included. However they don't, so from my perspective it's reasonable to remove a mechanic that encourages you to jump everywhere you go instead of walking. And btw acrobatics wasn't only used to cheat. It was used to get to places that you otherwise couldn't (thief). Its proper place, imo, is as a platforming skill, ranging from the basics of climbing and hanging, to advanced maneuvers like swinging from pole to pole, wall jumping, and wall running. Considering Skyrim has zero platforming elements, acrobatics doesn't make much sense. Maybe one day....