Technological progress should cause increasing economic inequality, because the bottom end of the scale is firmly anchored at zero (someone taking a vacation), while technology gives the top end ever more powerful levers. So the interesting question is not why economic inequality is increasing, but why for a few decades in the mid twentieth century the trend was reversed. There are probably several factors at work he…
It saddens me that you introduce the straw man of the zeroth percentile, "firmly anchored at zero". It wasn't in the linked article, which only talked about quintiles, none of which are anchored at zero. And with respect to these statistics, clearly someone taking an unpaid vacation is not in the class "production and non-supervisory workers". I have little problem with inequality. I do think there are some downsides…
Now, of course, correlation does not mean causation and it's perhaps more interesting what the true underlying causes are. But if inequality is such a strong indicator, it is worth wondering whether inequality isn't a bad thing in itself.