The New Economics Foundation suggests we work 40 hour weeks because that is the prevailing social norm, not because it is necessary:
The New Economics Foundation (NEF) says there is nothing natural or inevitable about what’s considered a “normal” 40-hour work week today. In its wake, many people are caught in a vicious cycle of work and consumption. They live to work, work to earn, and earn to consume things. Missing from that equation is an important fact that researchers have discovered about most material consumption in wealthy societies: so much of the pleasure and satisfaction we gain from buying is temporary, ephemeral, and mostly just relative to those around us (who strive to consume still more, in a self-perpetuating spiral).
The NEF argues we need to achieve truly happy lives, we need to challenge social norms and reset the industrial clock ticking in our heads. It sees the 21-hour week as integral to this for two reasons: it will redistribute paid work, offering the hope of a more equal society (right now too many are overworked, or underemployed). At the same time, it would give us all time for the things we value but rarely have time to do well such as care for our family, travel, read or continue learning (as opposed to feeding consumerism).
This reminds me of past visions where modern conveniences, like new appliances or flying cars or a a perpetually robust economy, would reduce the number of hours people would have to spend on “menial” tasks like housework and working. Alas, many of these things have not happened.
This group does raise an interesting issue: there are ideological reasons for sticking to 40 hours. This foundation suggests that working less would lead to more fulfilling lives full of relationships and time to pursue our true interests. I wonder how many Americans would really be willing to work less in exchange for less money or discretionary income.
I wonder if a movement toward this direction would require a respected company to make this change.