Of course it has, but those are hard fought gains that are primarily results of WWI, WWII, and the early phases of the Cold War, not productivity gains.

There is no natural law that productivity gains get handed down. Just compare the years 1950-1970 in the US, where life for the average worker improved greatly, to the 1980s onward, since when we've been in a downward trend. There's steady productivity gains over all that.