For the first time in American history, rapid increases in productivity have not been accompanied by corresponding gains in wages; at the same time, the minimum wage has lagged behind increases in the cost of living.It does not seem to me that increases in productivity should necessarily lead to increases in wages. It does seem that it should lead to an increase in standard of living.
Productivity gains should be sought. If a product at least equivalent in quality can be produced with lower cost in labour hours and source materials this is a good thing. As such the seller could make more profit per item. However in a competitive market the seller has an incentive to price the widget below that of his competitor to increase his market share. As such it may be that the profit per widget is unchanged though the cost of the widget to the consumer is less. Other manufacturers can introduce productivity gains and lower the cost of their widget, or improve the widget and sell a higher quality unit for the previous price.*
What I am suggesting is that increases in productivity should not automatically lead to an increase in profit which the socialists advocate be shared with the workers. Rather, in a competitive environment productivity gains should lead to decreased price.
But note that even though this does not increase wages, the standard of living can increase as these cheaper items cost proportionally less of one's income.
*I am aware that some productivity gains coexist with a lower quality item, though a significant drop in price may allow a much larger proportion of society to own items previously the domain of the rich. I am not advocating low quality, but some people may prefer a low quality item over the alternative—no item. And price drops are often proportionally greater than quality loss.