Kenflo was too scared to try to strike Aldo (due to his WEC history. dont forget this was the beggining of UFC Aldo). Kenflo put up an ugly fight, forcing TDs that would not happen and avoiding combat. We could see Aldo frustration in his eyes, not being able to put his gameplan (basically, trying to murder his opponent, as he used to do in WEC). This probably affected Aldo's mind that day.
anyway, Aldo evolved, and by A LOT. Today's Aldo would beat that Kenflo without difficulties.
McGregor looks good: strong, big, fast. Its just that Aldo is on another level. Maybe McGregor gets there at some point, but not yet. He will take a very very very hard beating.
Punchers chance.