You CAN complete the final raid in this game without saying a word. It matters not that its the easiest difficulty. Saying that groups happened means nothing, there was simply no way you could have completed the all the raids in Vanilla without a guild. Of course the game never forced you to make friends but if you wanted to get anywhere you did have to group, you did have to communicate and that's a good start to making friends. Today, its a single player game for a lot of people.