History
Throughout this past century, there's been plenty of mechanization & automation(...)( and more recently, A.I. - but that's a whole other discussion ): increase the efficiency of a job - make it take less labor to do the same amount of work. But instead of people working less, the market discussion "market", as in, the "invisible hand of the economy", or basically just a lot of businesses doing what they do to maximize profits decided to just produce more(...)( i.e. more goods and more services, per capita. The increased production counterbalances the increased efficiencies, so people on average don't work any less than before. ). Of course, in moderation this can be a very good thing - but we've long reached a point where it's harming the environment, with diminishing returns on quality of life. In fact, quality of life could be a lot higher if people didn't need to work as much.
What to cut
To have a world with a shorter work week, we need to be honest about what things we could produce less of.
Then, to put this into practice in real life, we would need radical economic changes. Discuss the ways that it could work.