What he said was that he used "average hourly wages", not total or aggregate.
...So the growth of CEO and upper management salaries offset the flat wages...
That's right, if we forget equality of opportunity and focus only on equality of results then we can say we're worse off. The economy as a whole is doing well while at the same time there are more people than ever who are saying their victims of inequality. Something else the essay left out was the fact that Americans are called 'capitalists' because they get incomes from working not only in the labor market but also in the capital markets. Total per person inflation adjusted incomes (after taxes) is at an all time high:
