In Israel where Shabbos is not a workday the irreligious not only don’t try to keep Shabbos but are even fighting to have buses running and shops and theaters open on Shabbos.
Also I am not sure if you don’t realize that Friday is the holy day for Muslims. So if there is to be a 4 day work week it would probably be Monday through Thursday, as Friday is the Muslim holy day Saturday is the Jewish Holy Day & Sunday is the Catholic Holy day