Yes, four-day workweeks will likely become the norm at some point in the future. It makes sense to work longer hours on just a few days and then have three days off. A longer weekend would allow workers time to complete outside errands and tasks so they don't interfere with the work week. They would also allow workers to more fully relax and therefore be more efficient and effective while at work. There are also likely to be economic benefits to only being open four days a week.
Many people who commute to work spend more than an hour a day just going back and forth to their job. It makes more sense and saves fuel to make only four trips each week and work a couple of extra hours on work days. Shorter work weeks make sense for workers and reduce emissions.
A corporation does not care about individuals. We are only cogs in the machine and as long as there are more replacements they won't care if we are ground to dust and most governments are tied to or completely bought by big business.
The only people who may be getting 4 day work weeks are specialists who can not be easily replaced and may be more productive overall. Your average worker however is expected to work more for less.
In 1930, the great economist John Maynard Keynes predicted the working week would be drastically cut – to perhaps 15 hours a week, with people choosing to pursue leisure as their material needs were satisfied. Yet despite rising living standards, we are working longer hours than ever before. So many, in fact, that they seem to invite workers to spend hours at their desks writing extended articles about how they should be working less. Yet the postwar compromise between big business and labor has been entirely rolled back. Now it is only a one-way street. It’s not a good time to be a worker. But more than that – why do we insist that the sum total of our lives is to be ‘hard workers’ – working in jobs we don’t like, in which we are actively disengaged from? With advances in technology, the 15 hour week is entirely possible – as our material needs are met. Indeed, it’s true that many jobs are increasingly redundant or superfluous, with machines able to do much of our work for us.
I can see 4 day workweeks going well for some places but less well for others. Countries like Sweden have gone the other way, so you work less hours per day more an average of more days per week over time. I think it is relative to the job type and culture, so I don't expect 4 day workweeks to become the norm.