I must also disagree with this. For certain, the actual battle between 2 players could be seen as taking less skill to accomplish. Certainly, a 1 on 1 PvE encounter takes little skill in general. However, the raid game in these MMO's takes a great deal of skill. A few people have to coordinate a large group of people to complete a task, and a good number of those tasks are by no means simple.
I know WoW has mitigated this to some degree, but Everquest would require a couple of strategic-minded raid leaders to properly deploy as many as 72 people against a target, with plenty of variables to take into account. In these situations, the raid leader is like the player in Starcraft, except they don't really know if their units are going to do as they're told. Sounds like some skill is required.