When you play a costumizable character, and you have dialogues with NPC's and freedom of choice, you are playing a role…. Every player character in Skyrim has to be the Dovahikin, but if you don't care about the main plotline you don't even have to know that - of course it depends on the time you spend playing Skyrim, but I have a second character with which I have played two, maybe three of the major quests (but not the main plotline) and I haven't killed any dragon, learned any shout or got involved in the dragon quest (or the civil war). This character is clearly distinct from my main character, which is a typical nord warrior, who was involved in all the major quests and the main plot. There are roles in Skyrim. There are no roles in Deus Ex: HR, where you MUST play Adam Jensen. It's a great game, I love it, but Deus Ex is not trully a role playing game because it does not have roles to play, just one.