Thanks for that. This study is much more nuanced and does not really concur with the conclusions from the article at all. The article says:

    Today, almost 90% of Icelandic workers benefit from a reduced working week of 36 hours

while the study says:

    The offer of shorter hours has been widespread. In the two years prior to being surveyed, more than half (59%) of workers were offered reduced working hours.

Or am I missing something?