I think the issue is that there are two conflicting populations on Hacker News: hackers/geeks/nerds in the traditional sense (who are here to talk about cool technology and such, and because the place is called "Hacker News") and entrepreneurs (who are here to talk about economics and politics and such, and because the place is run by a company that funds entrepreneurs).
Being part of the first group, it's a bit strange to me to see this sort of article on a site that's called "Hacker News", and I agree with the parent commenter that the article feels out-of-place here. Perhaps if it had some nifty technical details on flash bangs and their effects on humans (more concrete references to PTSD diagnoses, descriptions of temperatures attained by flashbangs and the physical effects of those temperatures on humans, even some possible elaboration on potential blindness caused by flashbangs) - in other words, things that hook into scientific basis (which makes nerds squee) rather than emotion/"ethics" (which doesn't make nerds squee) - would improve this.
On the other hand, I realize that my demographic is not the only one worth considering (regardless of whether I want it to be the only one worth considering). It's disappointing that articles with a dearth of technical description seem to be becoming the norm even here, but at the same time I realize that it's not disappointing to all of HN's users, so the best I can do is move on to a hopefully-better article (or stop using the site and find a place that actually lives up to my own expectations of something called "Hacker News").
Take, for example, this article regarding the hypothetical effects of extreme magnetism on humans[0], which was posted on HN yesterday and was well-received, relatively speaking. Unlike this article, it focuses on scientifically-tangible effects, and even revolves around a Futurama reference to boot; in other words, it actually appeals to the hacker/geek/nerd demographic described above. Had this article been written more similarly to this one (though probably without the humor involved, given the more serious tone and subject), it probably wouldn't be subject to derision as being "utterly political", and would instead be more universally appreciated by both demographics of this site (since it appeals to the interests of both those demographics).
The article's perspective may be "consistent with the norms of this website", as you say; my point (and presumably that of the parent commenter) is that it's only consistent with - at best - half of the norms and expectations. It covers an interesting subject (for the entrepreneurs, at least); it just needs to do so with more technical detail.
That all said, us nerds do post plenty of purely-technical articles with seemingly-boring subjects (made exciting by the technicality itself, to us at least), so I suppose it's only fair that a purely-non-technical article slips through every once in awhile.
[0]: https://gravityandlevity.wordpress.com/2015/01/12/how-strong...