Well, Fabian is saying all that only because they are true. All observers of the strong force between operating fans and flying excrements know that pieces of truth strung together do not always make the whole right.
Extensibility and Readability have little value when there is no need to extend and no need to read. These and other features of XML become critically important when speed and direction of changes are out of your control.
All of Fabian's arguments make little sense to a soldier who, in midst of a battle, finds that all of his bullets are wrapped in plastic.