That's true, but at least most of the developers have some training. Many people are thrown into management or wants to be managers, but never put any effort in

That's true, but at least most of the developers have some training. Many people are thrown into management or wants to be managers, but never put any effort into building the skill set required. There are remarkably few people who are just born as talented managers, probably the same number that are just naturally talented developers. All of the best managers I've had have all had some level of management training. Some got training while I worked on their teams and the improvement from no training to just a few months of training is pretty remarkably.