I'd be willing to wager that tighter or more hierarchical management structures are correlated with lower levels of engagement for the employees at the bottom. In other words- there are two ways to get people to cooperate: to use secrecy and threats as a lever, or to have a common myth or vision that everyone believes in. Increasing secrecy and mistrust might be a signal that the common vision has deteriorated. Of course it depends on the size of the organization too. I'd like to see a study confirming or disproving that idea.