Many organizations are still defining engagement as how satisfied people are with how they feel treated by their boss. This is a complex issue, beginning with how professionally, personally and socially unprepared many people are for their promotions to leadership positions.
The real gold in opportunity space here is not a call for better bosses, but for better connected teams. Teams have far more opportunities and resources than even decent bosses to help people feel valued and engaged. Teams can learn more by sharing more together than they could from their bosses. Getting engagement right is getting the culture of team connections right.