It's a ton of factors, and frankly, we can't discount that after WW2, we were the only major nation that hadn't had the sh*t bombed out of it, so a lot of our enormous economic growth post WW2 has to be attributed to the fact that we had an incredibly big advantage on everyone else because we still had infrastructure. Also having the majority of the population old enough to have lived through the Great Depression helped, as it was considered uncouth to display extravagant wealth, and so that helped keep executive salaries, while not low, at least not what they are today.
http://www.businessinsider.com/fortu...ker-pay-2014-6
Compare 1983 to now.
But, as Danzig said, the major thing is inequality, because the economy has grown (though not at the crazy rate it did post WW2) and yet worker salaries peaked in the early 1970s. The wealthy suck up most of the economic growth and "trickle down" is exactly what GHW Bush said it was before he drank the Reagan Kool Aid- voodoo economics.
And somehow, returns to shareholders became more important than lives of average people. I think of Hershey, moving a portion of their production to Mexico in order to keep share price high- why? If the company is not losing money, why isn't keeping a city running important and valuable enough on its own? Three thousand people here, including 900 in Hershey, lost their jobs as a result- all for a ten percent cut in production costs, in order to return money to... shareholders.
Cutting taxes on the wealthy just makes them hoard more money- they don't put it into the economy. Raising minimum wage puts more money into the economy because your average working class person has to spend everything they make on rent, food, gas, etc. That's good for the economy as a whole.
I don't think it'll affect employment rates, but it will do good things for the local economies, which is where the working class spend their money.