Before you have an aneurism on the notion of working 40+ hour per week, independent of 4 or 7 day, keep this in fact in mind:
996, this is how a recent Bloomberg article described the work schedule in China: 9am - 9pm. 6 days a week.   

Now that things aren't looking so gloomy, let's review what a "meaningful, value driven", 7 day work week may look like. 

Experiments for 4 day work week:
The four-day work week has clear attraction – who doesn’t want every weekend to last as long as possible? Unilever’s New Zealand offices are currently in the middle of a year-long four-day experiment. The governments of Spain and Scotland are planning trials that would subsidize employers that give workers an additional day off, and politicians in Japan and New Zealand have spoken favorably of the idea of a shorter workweek.  Still, four days’ work for five days’ pay will be a rarity in the landscape of American business.


Experiments for 7 day work week:

Forget 4 days, how about working 7 days a week? Let's take a look at three firms, who tried this experiment and their results from it (Source).

Employees at design consultancy Arup can work any day of the week. Arup’s 6,000 UK-based personnel can select to work their weekly hours every time fits them – even on a Sunday, if they want days off at some point of the working week. Arup trialed the 7 day concept in Liverpool in 2019 and Queensland, Australia in 2018. The Liverpool pilot was guided via three principles: impact on on clients, colleagues, and staff. In Liverpool, 82% of of workers flexed their hours, with a 1/3 deciding on to work on the weekend at least once over the 3 month trial. “Traditionally, weekend working builds resentment, as you be aware of you’ve acquired any other 5 days of work in advance of you – it will become a burden,” stated Andy Pennington, Liverpool office leader . “Taking the Monday or Tuesday off lets them have downtime to rest without guilt”. The advantage isn’t simply for staff but also Arup’s clients. It worked, with 9 out of 10 personnel announcing their productiveness elevated whilst giving them a higher work/life balance.

At gaming startup Stakester, all personnel have made use of its 7 day bendy working policy. “We find that those whose work is more focused and project-based, such as the more tech-based roles like developers, tend to work in evenings or weekends in irregular working patterns,” says CEO Tom Fairey. “Those with more customer-facing or managerial roles seem to naturally prefer working in the daytime with other members of the team.”

Design company BrightCarbon has presented such flexibility, although none of its 87 personnel work regularly on the weekend, says director Richard Goring. “Sometimes they might change their schedules for a deadline, but people generally want more weekend, not less,” he says. Instead, most labored longer hours to reduce their week to 4 days, with Monday, Wednesday and Friday the most famous days to take off.

While managing people’s working days is an extra burden, apps helps, such as Microsoft Outlook and Teams. Goring says it’s really worth the greater effort, as employees are happier and equally productive, which is good for retention. Goring suggested to treat people like adults and they’ll act like adults.

So What...

If you read between the lines, the argument here is not for a 7 or a 4 day work week, rather a flexible working schedule. If employees are trusted to align their firms success without forgoing their own well being, both will come on top in the end.