Managers in the middle of the food-chain are all about power-struggle and social games they play to out-compete each other.
That is especially the case for non-technical managers who don’t have a sense for the underlying technical challenges. They have all their bandwidth available for political positioning and social games.
It would be great if all managers where “serving the team” in the sense of your bullet points. But alas many don’t see it that way.
IMHO many startups are successful because they have a technical person at the top. Who is capable to understand, evaluate and positively reward technical work within their organization.