I must be thick as two bricks because I did not understand half of this book. Either Critical Theory is complex, or there is no way that an explanation can be simplified to my level of understanding.
My understanding is that Critical Theory has changed considerably over the past 80 or so years. Even though there was a central school for this theory, the theory has been hollowed out in recent years to be just something that conservatives can hate without understanding what the theory is supposed to expound.
The only time I got clarity was in the final chapter in which the author argues for a new direction for the development of Critical Theory as a continuation of the Enlightenment project. He argues that the lack of historical context has emasculated the critical theory development.
Instead of just opposing the establishment, critical theory needs to embed itself in the scientific method and engage with the world at large.