Welcome to life in practically any large US corporation. Most employees will never complain to HR, they may need some routine services that HR provides and that’s the extent of their interaction. But there are a few who do complain. If these are peer-related complaints, HR will work with the employees managers to resolve the issue. But let’s say someone has a problem with their manager. Maybe no one else has complained about him before, or if so the complaints appear to be isolated incidents. Let’s say he has a lot of positive feedback from his peers, manager, and other subordinates.

Now you, the complainant, are the problem. And oh boy you have some special life circumstances - yikes, you are like a loaded bomb dropped in the lap of HR. They are not in any position of power, they can’t set the policy for your department (rightfully - they are not in the know), so your boss holds all the cards. HR won’t dig to the bottom of anything, and a manager is more important that a developer. At best it’s he-said-she-said and ignored, at worst you are shown the door after some minimal make nice by the company to avoid future liability.

I think it takes a strong top-down initiative to avoid cultural issues like this at an organization. At some place as large as Amazon there are bound to be isolated incidents but to all indications this behavior is, if not encouraged (in some cases it appears to be), not actively discouraged and is hence tacitly approved of at Amazon. I’ve seen what it takes to get a bad manager moved or fired by their subordinates - it requires an outright coup. Rarely does such a thing happen and it’s not guaranteed to succeed. Whereas, a conscientious and capable manager can walk in and straighten something like this out in fairly short order, with minimal drama.