Manager are for managing low skilled workers that need supervision and help. The idea that you hire "the best SWEs" and then you have to slap a manager to oversee them like they are burger flippers is ridiculous on its face.

SWEs might benefit from some help from experienced technical leadership - someone to consult, get feedback from etc. and from bureaucratic assistance (help get paperwork out of the way), but typically "SWE manager" position is akin to fast-food chain manager in a SWE shop.