If you read the primary sources behind these headlines, studies find that knowledge workers who work 55 hours per week have the greatest creatively useful output of any amount of hours. Above 55 hours a week the output gets flat, reflecting no additional creative work utility. Up until 30 hours, the line is steep, hence where all the '6 hours per day' and '4 days per week' stuff comes from. But from 30 to 55 hours, you're still getting more done, it is just less per hour than the base 30 hours. One type of person looks at that and says 'I am less efficient over 30 hours, so why bother?'. Another type looks at that and says 'I get the most done by working 55 hours a week'. Both are true. Finally, these things are highly individual. People on the spectrum are able to focus on their special interest as much as 15-16 hours a day, which is not true of neurotypicals. So it is as an individual most important to know yourself, and in aggregate to know the median when setting policy.