I think another problem in schools is that classrooms are so isolated, which means that teachers are isolated from each other, too. The little world of a classroom can have a great culture and atmosphere, but it can also be pretty fucked up in a multitude of ways when one adult is overseeing 15-25 kids every day for a year. Honestly, it even gets kind of lonely as a teacher when you have so little meaningful time spent with peers.
A good principal steps into each classroom regularly, but more co-teaching and interdisciplinary studies would both be better for students as well as an improvement to teacher culture.