Have you raised your perspective on their problems with your manager?
If they don't care, leaving is not unreasonable (although the 6 months might seem like a ding on your resume). But usually, people know. Whether they know and just want to keep turning up and take the money without rocking the boat, or want to rescue it but don't know how.
Manager agrees on most of my points but, for various reasons, he cannot/won't change anything. All he can do is chase up people to set up a knowledge transfer meeting (when excessive meetings are just a sign of the dysfunctions of other levels).
If they don't care, leaving is not unreasonable (although the 6 months might seem like a ding on your resume). But usually, people know. Whether they know and just want to keep turning up and take the money without rocking the boat, or want to rescue it but don't know how.