I think there's some confusion here because often when talking about "flat" or "stagnant" wages people are referring to the idea that inflation outpaces wage increases (which is wrong, and the point I was addressing). But even taking into account how you're referring to "flat" wages, the logic is still wrong. If we take a worker today who earns the same wage, in inflation adjusted dollars, as a worker in, say, 1985, today's worker has a hugely increased standard of living, better healthcare, longer life expectancy, etc.