The problem with most social media that is “clingy” (non scientific term :) , the ones that manipulate so you keep viewing is that it adds to what is called “fragmentation” (scientific term) where you consciousness is being scattered, instead of flowing. Your brain is constantly being interrupted in the process it was doing. This is especially true when you constantly need to check your phone.
The structure and exposition of his arguments is what makes the text particularly engrossing, and I am loath to try to summarize what is best experienced within its intended context.
But I'll give you some copied paste from Wikipedia to get you started:
> McLuhan's insight was that a medium affects the society in which it plays a role not by the content delivered over the medium, but by the characteristics of the medium itself.