You are partially right. Activity points are a contributor to ranking and in the case of some that do not contribute they would eventually drop from the board. In the case of E, he or she was appointed early on and it would take a move from Agoracom to have the name removed. If no one brings it to their attention it will probably remain. I am the perfect example, as I was too busy to post during the summer and my points are right on the border line of 3.7. My rank is always changing as I fluctuate between 3.6 and 3.7.