Part of this could also be that the majority of us that still play this game don't have those excess hours that we used to in our youth. So, playing for 45 min -2 hrs is about the limit at any given time.

This can certainly appear that there's far more fair-weather play than there really is because people aren't logging in a different char, they're simply logging in for what time they have then logging out and trying again when they have more time.