The productivity gains have happened _because_ people were obsessed with increasing output. What's even more interesting is that we've had to adopt a consumer culture to keep the economy rolling in the face of an excess of supply. Marketing is an entire field of pseudoscience devoted to increasing demand to meet an artifically inflated supply.
Even the web is funded largely by advertising, marketing. Could it exist if we in the west had a classical eastern philosophy of not desiring more than we needed? Given that china invented practically everything, but got "nowhere" doing it until they adopted consumer culture, i suspect that the web wouldn't have happened.
Admittedly, China didn't "go nowhere". Late Medieval China had living conditions better than any the pre-industrial and industrial West managed, while working less than the post-industrial West does today. Only the onset of social democracy and post-industrialization drove living standards up to what the Chinese enjoyed for ages.
Admittedly, they mostly managed this because large portions of their land area could naturally support plenty of people without too much work put into agriculture.
There are significant constraints on people's ability to choose. Many people, particularly in the upper-middle-class, would choose lower income for lower hours if it were an option. Of course, many others wouldn't. But if it were common for large companies to offer, say, a choice of working a standard workweek for regular pay, or a 32-hour workweek with every Friday off for lower pay, quite a few people would take the 4-day-week option.
This is one of the problems, the absurdities, of economic inequality.
The upper-middle class, in America and parts of Europe at least, is the highest anyone can rise by working for other people. It is surely a rat-race to get there, although a fairly meritocratic rat race. The result is that "upper-middle class" jobs are very highly competitive, and tend to remain at a highly competitive equilibrium level of salaries and working conditions even if there's an apparent skill shortage within the particular industry itself. Because after all, there might be a shortage of programmers, but if you don't want to work long hours, what're you going to do, get a fast-food job?
Thus we get ourselves an entire class of people who, by most standards, are rampantly overworked, but at the same time quite sufficiently paid. If only they were to stop competing with each other for status (inside and outside the workplace), they might be able to put an end to the poisonous equilibrium of the 50-hour workweek, simply by agreeing that the last $20k/year of salary isn't that important.