Honestly the dramatics over a slight change in how the playerlist works are bordering on the absurd, at the very worst case this change is slightly less convenient.
However Antonio did hit on at least one of the issues, though somewhat poetically it was raised as a counter to this change, people not logging. The server populace isn't dropping because of empty space and (currently) unused factions, its because people are waiting for activity to cross their paths. The evidence stands before you in this very thread, all the complaints hinge around not being able to find anyone in certain areas yet completely ignore the fact that they themselves could log in to cause the activity.
If folks like Protege find it slightly more annoying to open Disco just to check the playerlist then perhaps they should just play since its already running? If you want population, you need people.