We've propagandized a generation of people into believing that there has been no wage growth for 40 years when the deal was actually that there were falling wages in the 80s, stagnant wages in the 90s, and growth since then (with a recession after 2008 that has been fully caught back up to since).
Which is "real average hourly earnings for production and nonsupervisory employees," and is the source of the graph that purports to show stagnation between 1973 and 2017 (it has in fact grown higher than 1973 since then).
Why that particular graph? Well, it excludes wages for "the bosses" and such, so perhaps it shows something more like the average person's experience. But also, I think it's cherry-picked because it shows a particularly grim view. For example, here's the real median household income chart instead:
If you want, you can find income by quintiles. In like the 90's and 2000's, the rise of inequality, top quintile earnings growth was much higher than bottom four. But that largely stopped in the 2010's and has actually reversed in the 2020's, with bottom quintile growth now the strongest.
Long story short: income is complicated, there are a lot of ways to dice everything. But if you look into the claim that "wages have stagnated," you will overwhelmingly see the "real average hourly earnings for production and nonsupervisory employees" data line. And regardless of how good or bad that particular choice of data is, it doesn't actually show stagnation -- it shows a big drop in the 70s and 80s, largely stagnant 90s, and then growth since then.
