Part of the problem is player attitude, but we all know John Gabriel's Greater Internet F@$!wad Theory. There isn't much that can be done about that issue, so the best solution is to find the core of the problem within the games themselves.
At the core, the issue is about soloing and how it has become the de facto design focus for most developers. One of the few development teams who seem to be focusing on new group experiences and powerful guild tools is EA Mythic. A point Ethic makes in his post is that developers should be focusing on giving people reasons to really want to group together. I fully agree with that sentiment, but don't get me wrong when it comes to solo play. The solo experience is important as well, but it is not the essence of a massively multiplayer game.