Because it's a big fat lie and false conditioning of the mind. The workweek is 80 hours.
Here's why:
From the 40's to far into the 70's the 40-hour-workweek was promoted as a huge win for workers, which was true back then. Mostly men worked 40 hours, went home to their wife (vast majority not working), came into a clean house, food was on the table and most kids were raised civil and properly.
The house was nice, big enough, a car was paid off instantly and college funds for their kids was no problem. About 35%-55% maximum of the income was for basic necessities a.k.a. mortgage, utility bills and groceries while the rest was for a nice life or savings.
Meanwhile there were years when +20% income growth after another was normal, because inflation was at that same rate. In te late 70's seventies something happened and it accelerated in the late 80's and the 90's: women went to work. (No offense, women should be able to work and men should be able to keep a household going when they want)
But it resultated in todays standard: 2 adults per household working a grand total of 80 hours instead of 40 hours like in 1973. No time (or money) for raising kids properly, household shores go to the weekend so no time to take trips or really relax, and about 85% of the total household income goes to basic necessities.
We also have to take into account that robotization, software and automatization should have become to the workers rescue regarding even less working hours, but the opposite happenend.
Public transit is dirty and still in declining state. Public safety is a laughing stock. But yeah….we now have a mobile telephone and a flatscreen. WoW!