This is the same problem as people working 40 hours a week have competing with people working 80 hours a week have; they mostly can’t. Even if the last 20 hours are so marginal that really, you might as well not have bothered the person who worked 80 hours a week got 1.5 times as much done, and in any job that isn’t totally routinised the knowledge and skills gained from working compound. They compound faster for those who work more hours.