Everything is highly situational. I couldn't tell you whether it's better to have your most valuable ICs managed by the best managers, or whether the most valuable ICs need only limited management and you should have your best managers focusing on improving more junior engineers.

(This assumes that the "managers" are strictly people managers. Often, managers might do some or all of managing teams, products, releases, people, or technical leadership. It certainly wouldn't be unheard of to have a manager's team include an engineer far senior to the manager.)