That's a popular opinion, but how do you quantitatively prove it? While the formal education of a population may correlate with wealth, I think it would be harder to prove a causal link.
It's about what is necessary for DEMOCRACY to work well. I don't care what provides a higher ROI to some rich owner-class people, I care about a society that represents its people.
It really depends on what you mean by that. Plenty of people get bachelor’s degrees with little to no civics or history education included. And historically, college degrees were rare. Only 28% of the Silent Generation had any college. Now, 67% of Millennials do. Did democracy not function before?
However, to the extent that education enables better income opportunities I agree. Education can reduce economic inequality which is a huge barrier to social cohesion and civic trust. However education isn’t the only path to better wealth distribution.
Democracy gets harder the more technologically advanced the world is.
In the decades of newspapers and limited information it was much easier to control information, placing the burden of information flow on a limited set of journalists.
Now that burden is put on each and everyone of us with social media and other alternative media. People from the Silent Generation are drowning in todays information age.