"It is notable that the era of peak democracy in the Anglophone world, the mid-20th century when the working class had the most political power, was also the peak of literacy."

That's the most significant line in the article. That was the peak of union power, and unions routinely had meetings and votes which mattered. What organization do you belong to today where the members can fire the leadership by a vote? When did you last go to a meeting run under Roberts Rules of Order, as almost all union meetings are?