"Teachers talk endlessly about methods of engaging children"
Unless they are faced with a child who spent all of their time learning instead of doing mind-numbing homework assignments. Then you'll hear teachers talk about how they have a student who is wasting his talent and how shameful it is that someone who can handle more advanced material is getting failing grades (even though they are the ones giving the grades). Teachers may talk about trying to get students to think "outside the box," but when a student actually does so they are punished for it.
Our education philosophy is based on attacking independence and ensuring compliance, and our teachers show it. Rigid structures are enforced everywhere in school, explicitly and implicitly. Assignments are rigidly structured. Classrooms are rigidly structured. Daily schedules are rigidly structured. Grades, which become the purpose of school for many students, reflect how well students follow instructions more than how well they understand the material.
"This sort of Prussian, militarized school setting is a dystopian fantasy."
Well, maybe so, but in dystopian fiction the hero is typically one a small group of people who can recognize that anything is wrong with the system; everyone else believes they live in a utopia. Perhaps school truly is dystopian, and only a minority of people can actually recognize the existence of a problem.