I think peoples are bored by the game, there is still a lot of things to improve but actually there is a long time nothing new came.
You can see it with other video games, when a game is getting old and no new DLC has been released, there is less players in the game, but when a new content is released there is a lot of players coming back.
Actually, I am hesitating about making a break, leave the game and come back later, I only manage 1 team, so I don't think that the fact that some owners with too many teams don't care about all of their teams is the real, or at least the only problem... I think it's about weariness with a game that everybody knows, and that everybody knows the actual limits of the engine...
I think the game needs something new to be released.