These are the relevant links for the idea:
http://www.econtalk.org/archives/2017/05/tyler_cowen_on_1.ht... (about half-way down, search for "casualness")
> * But what I find striking is societies with a lot of upward mobility often tend to have strict dress codes. So you see this today with Mormons, at Mormon businesses. You see it in Japan in its heyday years--you know, the businessman or journeyman suit, they more or less all looked the same. There's something about upward mobility where actually clothing is not that casual and one is being more formal in trying to impress; and that is a [?]. But the thing about being casual is it actually makes it harder for people to prove themselves.*
And a follow-up: http://marginalrevolution.com/marginalrevolution/2017/05/inf...
> When I [a correspondent, not Cowen] was a young associate at the biggest law firm in Rome, casual friday was the time when my Sicilian provincial middle-lower class background was most transparent. I didn’t have the money for smart but impressive casual clothing. But above all I didn’t have the cultural and social capital to know how to dress casual in the right way.
In general, social norms often play a substantial role as a level playing field. The people who benefit from their removal are those who can quickly understand and adapt to the unarticulated, informal rules that govern all human interaction. I'm happy I don't have to wear a suit and tie every day (and slightly sad that I never have, but that's a different discussion), but let's not pretend that "no dresscode" is actually to be taken literally if you have any intention of advancing in the hierarchy that we pretend isn't there.