Welcome to last week, Captain Obvious.

The community itself is not dying. The game itself is just going very slowly down. Sponsored events, such as JDC, helps it stay alive by getting players' attention and bring the remaining active Jazzers together. Don't forget that ClanBase just granted the game a Ladder, which certainly will help keeping it more active.

Try to arrange games with some of your friends, rather than surf for games. It's much easier that way.