The argument in "Amusing Ourselves to Death" is not that the written word enhances reality, it is that it engages critical faculties by forcing the reader to contend with the argument advanced by an author. This article suggests that the written word is a crutch for thought, and thereby diminishes our ability to get at reality. These ideas are not exactly opposed, but there is a certain discordance.
It's written word, but its metaphor is the same as the metaphor of mediums like TV.
To be honest, I think this is a general weakness in Postman's work. He talks a bit about the difference between pre and post-telegram writing, but he lionizes all 18th century writing despite there being tons of different forms (pamphlets, books, novels) that don't have the same intellectual value imo.
I got that too. And yes, also ironic for the author (a writer of some kind) to be advancing a seemingly anti-literary agenda.