I don't know why you presume that because we are mostly 25-35 something White males a reasonable proportion of us are not deaf, gay or disabled (one of the top level posts is by someone who will soon deal with being perhaps limited to communicating with the world via computer)

I smell a whiff of that weird American memplex for minority and diversity that my third world mind isn't quite used to, but which I seem to encounter more and more often, you know the one that for example uses the word minority to describe women.

Also I decline to invitation to defend this community for lack of diversity, I don't see it as a prior a thing in need of a large part of our attention. Rationality is universal, however not in the sense of being equally universally valued in different cultures but certainly universally effective (rationalists should win). One should certainly strive to keep a site dedicated to refining the art free of unnecessary additional barriers to other people. I think we should eventually translate many articles into Hindi, Japanese, Chinese, Arab, German, Spanish, Russian and French. However its ridiculous to imagine that our demographics will somehow come to resemble and match a socio-economic adjusted mix of unspecified ethnicities that you seem to hunt for after we eliminate all such barriers. I assure you White Westerners have their very very insane spots, we deal with them constantly, but God for starters isn't among them, look at GSS or various sources on Wikipedia and consider how much more a thought stopper and a boo light atheism is for a large part of the world, what should the existing population of LessWrong do? Refrain from bashing theism? This might incur down votes, but Westerners did come up with the scientific method and did contribute disproportionately to the fields of statistics and mathematics, is it so unimaginable that developed world (Iceland, Italy, Switzerland, Finland, America, Japan, Korea, Singapore, Taiwan ect.) and their majority demographics still have a more overall rationality friendly climate (due to the caprice of history) than basically any part of the world? I freely admit my own native culture (though I'm probably thoroughly Westernised by now due to late childhood influences of mass media and education) is probably less rational than the Anglosaxon one. However simply going on a "crusade" to make other cultures more rational first since they are "clearly" more in need is besides sending terribly bad signals as well as the potential for self-delusion perhaps a bad idea for humanitarian reasons.

Sex ration: There are some differences in aptitude, psychology and interests that ensure that compsci and mathematics, at least at the higher levels will remain disproportionately male for the foreseeable future (until human modification takes off). This obviously affects our potential pool of recruits.

Age: People grow more conservative as they age, Lesswrong is firstly available only on a relatively a new medium, secondly has a novel approach to popularizing rationality. Also as people age the mind unfortunately do deteriorate. Very few people have a IQ high enough to master difficult fields before they are 15, and even their interests are somewhat affected by their peers.

I am sure I am rationalizing at least a few of these points, however I need to ask you is pursuing some popular concept of diversity (why did you for example not commend LW on its inclusion of non-neurotypicals who are often excluded in some segments of society? Also why do you only bemoan the under-representation of groups everyone else does? Is this really a rational approach? Why don't we go study where the in the memspace we might find truly valuable perspectives and focus on those? Maybe they overlap with the popular kinds, maybe they don't, but can we really trust popular culture and especially the standard political discourse on this? ) is truly cost-effective at this point?