Earlier quoted context omitted.
Average worker compensation has nearly doubled in the past 20 years.[1] Almost exactly in line with aggregate productivity levels.[2] What I'm guessing you're referring to is median household income. Which is a quite different number than mean worker income. The former has stagnated relative to the latter primarily because a massive number of prime-aged workers, in particular young men, have dropped out of the labor…
Adjusted for inflation, income growth is 0. Capital is capturing all the productivity gains. https://www.pewresearch.org/fact-tank/2018/08/07/for-most-us...
Mean wages have closely tracked productivity metrics. Median wages have fallen relative to mean wages. That strongly implies that the issue isn't decoupling between wages and productivity, but faster growth in the output of high-skilled workers relative to low-skilled workers.
This is confirmed by the empirical research[1], which shows that 61% of the divergence between median wages and productivity has come from income inequality between workers. Only 25% has come from rising corporate profits.
[1]https://www.epi.org/publication/ib330-productivity-vs-compen...