You don't. At least not as you discuss here. (There is the possibility of answers to a question in one community having relevance to a different question asked on another community; that's a separate case.)
Ignoring for a moment the specific question you're referring to, it's extremely rare for any question to be equally applicable across multiple disparate fields without any changes whatsoever.
Even when a question can benefit from the point of view of multiple different fields of expertise, it's almost always the case that the focus of the question will be different between them. Thus while the reason for asking might be one and the same, and one might add links between them for context, the actual question being asked will differ depending on the target audience, and thus so will the answers given.
If you have a question that's general enough that you could equally well ask it to a software developer or a linguist, then you should probably ask yourself if the question is specific enough to render useful answers from either.
Going back to the specific question you're pointing to, you ask:
What are the linguistic pressures behind categorization?
What linguistic-psychological motive would "point" a person to choose a plural or a singular name?
Those hardly sound like questions that a software developer would be particularly qualified to answer. Those software developers who also have an interest in linguistics, and thus might have a chance of answering them, will probably check out a linguistics-related site as well out of personal curiosity if nothing else; thus, they will see it if it's posted in its proper location given the focus of the questions being asked.
Now, if you were to take the seed of that question, and instead ask for example why one would prefer to name computer-based collections (database tables, list variables, directories/folders, ...) in either singular or plural, now that might be something that a software developer might be more qualified to answer as compared to a linguist. It's also a question that might teeter too close to opinion-based for a fact-based answer to be possible to give, and thus might end up being closed for that reason.
But in neither case would it be the same question.