That is a good heuristic for future pain and frustration.
Managers who are good engineers don't always manage well. Managers who have never been engineers are usually worse.
> When you don't know whether a direct report is doing good or not because you don't understand what their doing, by definition you cannot manage them
Especially middle managers, if they are not the owner and have their own managers on top of them, who also don't know how engineering works, there will be trouble. Because they are stuck in the middle. They have to please the ones on the top, without understanding how the programming actually works. So they'll make promises then turn around to you and tell you to work 70 hour weeks.
> So long as the "people managers" are biz guys who don't understand engineering
It is hard. The more time they spend managing and coordinating the less time they spend writing code. The less time they spend writing code the further they move from understanding what is involved. They just forget, or practices and tools change.
Besides leadership is the key. That is as much learned as it is just a personality trait. It ties into how they relate socially to others, how they solve social and political problems. It requires empathy, but also harshness and coldness at times. I can be learned by I wouldn't discount it too trivial.