Wow, I expected a downvote or two, but -15 seems like an unusually severe Less Wrong sense-of-humour-failure given I was making a tongue-in-cheek reply to a comment with a not-very-serious tone itself.
Less Wrong is a tough audience for a comedian. Only the cleverest (i.e. least obvious and most unexpected) jokes draw upvotes.
A useful rule of thumb: Expect to draw a downvote from everyone who thought of your joke themselves, but then decided not to post it because it was too obvious.
Less Wrong is as a community extremely nerdy. That's true for almost any definition of "nerd" that captures anyone's intuition for the word. However, to a large extent, many aspects of nerdiness are not connected to rationality at all, even though nerdiness may be associated with more rationality in some limited aspects. For example, fantasy literature is probably not in any deep way connected to either intelligent or rational thinking except for historical reasons.
Yet LW is full of references to science fiction, fantasy literature, anime and D&D. In one recent example, a post started with an only marginally connected tidbit from Heinlein. Moreover, substantial subthreads have arisen bashing aspects of other subcultures. For example, see this subthread where multiple users discuss how spectator sports are "banal" and "pointless". I suspect that this attitude may be turning away not only non-nerds but even the somewhat nerdy who enjoy watching sports, and see it has harmless tribalist fun, not very different than friends arguing over whether Star Wars or Star Trek is superior which has about the same degree of actual value here.
There's a related issue which is a serious point about rationality and human cognition: Our hobbies are to a large extent functions of our specific upbringings and surrounding culture. That some people prefer one form of fantastic escapism involving imaginary spaceships isn't at some level very different than the escapism of watching some people throw and catch objects. Looking down on other people because of these sorts of preferences is unhelpful tribalism. It might feel good, and it might be fun, but it isn't helpful.