These two men are in a bitter fight against all the dominating forces of their time which they believe are purposefully opposing public enlightenment. Since Adorno and Horkheimer accept the modernist view that humans ought to strive toward progress, they naturally believe that mental and religious enlightenment is the most powerful way to move the culture forward, but they notice that government systems, economic systems, and even academic powers are opposed to enlightenment.
They also accept in true Vienna style that meaning and enlightenment are derived from good stories and narratives that speak deeply to the human experience. By encountering the essential truth of the human experience, a person can become emotionally enlightened. This puts them at odds with the new schools of philosophy that were rising in power. Post-modernism of course famously rejected these ideas wholesale, but also, the Logical Positivists were enemies of these ideas about human ethics, essence, and enlightenment, and together, those philosophical schools changed the university landscape of Europe and the West.
Then there are the government and political issues that withhold enlightenment form the people by replacing true narrative with a replacement in the public realm. For Capitalist countries, the replacement is made by advertisement. For Fascist countries, the replacement is totalitarian, replacing art with straight, unbridled propaganda.
