It sounds like the principle you're bringing in to play here could make anything count as xenophobic, so long as it involved a negative opinion and more than one group. This is dangerous because there are many opinions which are not xenophobic and are useful: misclassifying them as xenophobic introduces the error of "useful xenophobia," which is a very dangerous mistake.
Edit: I think I've debugged the issue. I'm treating these things like they're true and were discovered independently, and you are treating them like they're false (or at least unjustified) and spread socially. I know that in my case I've learned to not like science journalism first-hand, by reading articles while knowing about their subject matter (an incredibly surreal experience).
People are social animals, susceptible to group-think. There’s really nothing wrong with that, as long as we’re willing to accept the possibility and don’t succumb to the firehouse effect.
>It’s so common on HN for example, that it is frankly impossible all of its purveyors came up with the idea independently. That’s true even if the collective complaints have a basis in fact.
If our complaints have enough of a basis in fact, then why would it be unlikely for everyone with the right domain knowledge to realize the same thing? The idea that something can be factual but also still somehow based in groupthink belies an understanding of the word that leads back to another common criticism of the humanities...