The author's article critiques British popularizers of philosophy by saying:
In their bland readability, these books defeated their own avowed project of getting everybody interested in the great philosophers, by confessing how unreadable the texts of Kant and Hegel themselves must be.
Personally, I think philosophy should be comprehensible but not necessarily possible to make into slogans, i.e. not comprehensible by the intellectually lazy. On the one hand, any true and applicable idea should be confirmable in any number of ways, and can be put into nice examples, anecdotes, applications. (I'm thinking here of, say, how to describe what phenomenological analysis amounts to or what Kant's or Mill's ethical theory is about.) On the other hand, there's no reason to think that the advanced applications of even these ideas won't be aided by a newly grown conceptual system that takes time to decipher. I agree, then, with Blackburn who is characterized in the article as saying "making philosophy accessible should not be a question of simplifying it but of bringing people up to its level."