OTOH I'm not sure I've actually ever seen the same person making that argument and also oppose immigration (unless you count trolls like James A. Donald)
Um, the main argument against immigration is not based on the work they do but on what else they do, e.g., commit violent crimes or vote against the policies that created the economic prosperity that enticed them to immigrate in the first place.
FWIW males also commit a vastly disproportionate share of violent crimes. And in plenty of places immigrants aren't allowed to vote, unless they get citizenship first (which usually requires many years and a civics exam).
EDIT: Also, you seem to be implying that voters have non-negligible actual power to affect economic policy, which is preposterous these days.
LW readers have unusual views on many subjects. Efficient Market Hypothesis notwithstanding, many of these are probably alien to most people in finance. So it's plausible they might have implications that are not yet fully integrated into current asset prices. And if you rightfully believe something that most people do not believe, you should be able to make money off that.
Here's an example for a different group. Feminists believe that women are paid less than men for no good economic reason. If this is the case, feminists should invest in companies that hire many women, and short those which hire few women, to take advantage of the cheaper labour costs. And I can think of examples for groups like Socialists, Neoreactionaries, etc. - cases where their positive beliefs have strong implications for economic predictions. But I struggle to think of such ones for LessWrong, which is why I am asking you. Can you think of any unusual LW-type beliefs that have strong economic implications (say over the next 1-3 years)?
Wei Dai has previously commented on a similar phenomena, but I'm interested in a wider class of phenomena.