Well, yeah, if you have an essay about infidel-killing, having the subheading for the part where you lay out the case for doing so describe said case as "pretty air-tight" isn't exactly a heinous offence.
And you're kind of skipping over considerations of what values Less Wrong tends to have. There's a lot of effective altruism material, members of the community are disproportionately consequentialist, are you expecting little asides throughout the article saying "of course, this doesn't apply to the 10% of you who are egoists"?
describe said case as "pretty air-tight" isn't exactly a heinous offence
The question isn't about the offence, the question is whether you would agree with this thesis in the context of an essay about islamic jihad.
There's a lot of effective altruism material, members of the community are disproportionately consequentialist
Neither of these leads to vegetarianism. Consequentialism has nothing to do with it and EA means being rational (=effective) about helping others, but it certainly doesn't tell you how wide the circle of those you should help must be.
I'm currently unconvinced either way on this matter. However, enough arguments have been raised that I think this is worth the time of every reader to think a good deal about.
http://nothingismere.com/2014/11/12/inhuman-altruism-inferential-gap-or-motivational-gap/