Famous SF writers love tossing around obscure words. The more obscure, the better, too; as if knowing a word no one has used since the 18th century or is only applicable if you’re translating a passage from a Dead Sea Scroll makes them Special.
The word that so upset her? Luddite. Now, there’s no shame in not knowing the word, but it’s not particularly uncommon, let alone “obscure”; I’ve known it as long as I can remember, and so have most of the people who commented on the entry (including Lynn, from whom I got the link). What particularly struck me was the idea of a writer complaining about the use of a word she didn’t know. Personally, I’m always grateful when I run across unknown words; the wordhoard can never be too full.
Update. Further discussion at Byzantium Shores and Reflections in d minor (which also has a post on big words in general).