In this sense, Westerfield's reading is the more 'blinkered SF fan' one, and yes, does come across as self-important. However, I don't think you'd need to look far to find his equivalent in lit-fic land.

Indeed. Would Niall quote them approvingly though? I think the strong negative response to Westerfeld's piece here can be explained my the fact it is an almost textbook example of the things that piss off non-fan SF readers (more than a few of whom read this blog.) When you use the term mundane you sound like someone using using the term muggle, ie. arrogant, bigotted and ignorant of the world.

In the comments Westerfeld himself explains what motivated him to right his response:

Indeed, I wasn’t being fair at all to Mr. Non-sf-Reading Reviewer Man. I was merely ranting against the torturous transition from the con-space to the real world, which I feverishly imagined to be embodied by one tiny line in the NYTBR. I got no beef with Mr. Knight, and am sure he doesn’t really see the operations of language and storytelling sophomorically.

The diagnosis is clear: fandom poisoning.