I think that’s the age when most workers start moving into positions where they no longer need to actively solve hard, abstract problems, and the brain starts t

I think that’s the age when most workers start moving into positions where they no longer need to actively solve hard, abstract problems, and the brain starts to atrophy just like a muscle that gets no exercise. Combine that with an increase in stress levels due to no longer being able to directly ensure the success of work and you get a managerial brain grinder.