As a history teacher in high school, I think this kid’s letter is the visual representation of awesome. At nine he is coherent, asking legitimate questions and pointing out problems. The real problem is the teacher’s dismissive comment that didn’t actually say anything. The teacher is disappointed? Maybe they should…

You hit the nail on the head about retaining unhappy people. There’s no real benefit to locking someone down that wants to work elsewhere; poor supervisors think someone leaving the team reflects poorly on them while good leaders think moving people to positions where they’re happy is a net gain for the company.