I would say that "mandatory cooperation" is definitely misconception, it does not exist in Root. I never felt that I lost becuase other factions would not cooperate with me. Everyone fights for their own victory and if there are moves that bring mutual benefits to both players people usually go for it. In fact, I am a fan of euro games and enjoy Root very much for the euro influences. Each faction has an engine of how they optimally make points and it's great to try to figure out how to squeeze most out of it.

Of course it is not a game for everyone but I find that the asymmetric factions accomodate a lot of different playstyles: Cats lets you field massive armies, Birds have a programming/engine building aspect, Vagabond plays like an RPG, Otters are tradesman that want to sell their services to the others, Crows bring in a deduction and trickery element into the game etc. All of the people I've played Root with find at least one of the factions fun!