While that's true in a very realistic sense, i take issue with it because our modern economy is based in large part upon technology and theory developed by STEM workers. If you don't have people doing the hard work of pushing civilization forward, then there's nothing for the managers to manage. If America wants to remain a dominant force in the global economy, we have to be doing the things we were, educationally, in the mid-century period.
But this stuff is hard and makes your brain hurt, which is why we've experienced the "financialization" of the economy. It's just too easy to make money by moving money around these days.
This quote is quite apropos, as the very thing that has allowed the proliferation of jobs in finance is the middle class largely not being in control of their financial destiny: all the money is floating (or perhaps being sucked) up. So I need to add another qualification: doing such a job is similarly low on the totem pole in terms of societal good. The goal isnt to provide a good or service as such, only to make more money (whether for the managers or their shareholders, who are, again, largely affluent to begin with.)