As a manager in one particularly toxic org, you had to strike a balance where you showed constant forward motion, but not too much. Too little and you'd be tortured with meetings with a PMO, too much progress, you'd be declared a genius and the PMO would either appoint you as a "champion" to get shit done or take your people away.
Not really. They're ammo for whatever the manager wants to do with the target of your review. Management can spin this feedback to fit the agenda. They can also serve as a paper trail for managing someone out.