> You can certainly see some countries (e.g. Scandinavia, or Australia, or even Canada) finding a different balance point than other countries (e.g. the US).
Three very resources rich regions. They are exploiting their natural resources to compensate for their (relative) low productivity.
> When 8 hour work days were introduced was there some sort of sharp drop in productivity or innovation or standard of living? Or when the work week was shortened to 5 days from 6 days? I don't think so.
Yes there was a drop, if you consider everything relevant. When the 8 hour work day was introduced new workers were still being added to the workforce. Almost half the population in productive age joined the work force in the later part of the 20th century alone and women were for the most part not working when the 5 day work week became a thing for example. Individually the work hours came down, but as a whole we work much much more today.
But we don't have that luxury now, we don't have an untapped work force to lean against. And of course, the elephant in the room: our declining and aging population. Fewer and fewer working adults will have to provide for an increasingly large number of retirees.
The situation particularly in the west is dire. Pension funds are at very high risk of collapsing almost everywhere and the solution will not be to work less. Maybe, because politicians are politicians, the 4 day work week will be a thing, but retirement will creep into the 70s, it's already being proposed in some countries.
Increases in leisure time will be only on paper, done only in exchange for votes.