Around Germany and Greece there were other countries. They went by names like frugal four and PIIGS. They forced "austerity" and stricter working hours onto indebted countries to save their own banks.
The colours on this map show well that northern "productivity" is not about working hours, but about other topics that did not get addressed. Among these topics are also tax heavens (think the Netherlands) and money laundering (think Austria's special relationship with Russia).
So it was nothing more than poor political leadership without vision.
OP doesn't seem to understand how these data are compiled.
In most tourism-related jobs (e.g. restaurants), people don't count their hours.
This completely distorts the data for countries like France.
In Scandinavian countries and Germany, is common for 1 parent to work 50%. They also earn 50% (actually even less). This also distorts the data for these countries.
Finally, many of these states are about contractual hours. Not actual. If you work overtime, this is not accounted for. If you don't declare employees, is the same. And if you don't work, while being at work, i it's still counted as work.
Final word about the critics of Spain, Italy, Portugal and Greece. Most of these people criticized the fact that they take long breaks and "waste time" while at work (=do chitchat).
They usually don't realize, that while Germans commonly leave work around 5pm, people in other countries stay until 6, 7 or even 8pm.
For the chitchat part, it's mainly that they don't value it.
Didn't get too offended by idiots ;-)
So working 50% distorts the data by reporting 50% of the hours?
It's opposed to when one party stays at home full time to take care of the children, it's not counted, and doesn't detract from average work hours of the people that have work.
It's probably similar in other countries, but here (Denmark) the norm is that women work full time just as much as men, and this has been the case for decades. Also our unemployment rate has for years hovered around the theoretical minimum.
The retirement age has been increased, and is now about 70 years, and for younger generations it is set at 74!! IMO that's too high, and I don't believe the argument that it is necessary. But that's what our government has done.
So as a population I'm pretty sure we probably have reasonably high average rate of work hours per capita.