The question is short, yes, but it is very to-the-point and asks for a straightforward answer. It was put on hold, and the comments are begging for more information. "Please tell us exactly what the meteor is made of," for example.
I am not going to claim that question is high-quality, as it is not. It might even be low quality (Debatable, and my opinion is that it's more "simple" than it is "low-quality"). However, if the question were much more specific, it would be so narrow that it would beg for low-quality one-liner answers that just show the calculation and answer. The way it is, it is specific enough that it is answerable, but it is open enough to invite good quality answers discussing the aspects involved (material, solid vs loose chunks, time until impact, etc., all of which affect the answer).
My question is not "Why was that question put on hold?" Rather, I am making a comparison between that question and other common questions on Worldbuilding. The sample question above was put on hold because of its lack of details, yet there are very, very, very many questions asked all the time which are much more lacking in details than the sample question; in fact, this might be true of the majority of Worldbuilding questions. This is often true even for long questions which provide lots of details (often extraneous details, but they set the tone for the question so that's ok); they are still often wide open.
The "how much explosives to take out a meteor" question, after its edit (which came before the hold), is fully answerable. Details such as "What material is it made of?" are important enough that they can change the answer significantly, but only quantitatively; the answer is still a calculation, and a good answer would provide a range based on best-case/worst-case anyway and so are not needed in the question.
Right now, on the "front page" (or whatever you call it), there is: A government of the near future is trying to send a self-governing crew to populate an earth-like planet 100 years away and How big could an alien-made object on the far side of the moon become so that discovery still can only happen by accident? and If Earth's gravity suddenly became stronger, how would we cope? and... well, I was originally going down the page to include all the current questions which are left open to more interpretation and opinion, need more extra information than the initial sample question, and are generally more open-ended than the initial sample question; but at this rate it looks like it really is most of Worldbuilding questions, at least by the sampling pool of the current questions.
This is actually quite common around here, that questions are targeted for action where the rationale actually explains a large portion of Worldbuilding, and the targeted questions are not infrequently less broad than the others around it.
My point is just that the hold/close reasons such as "too broad" seem to be used somewhat arbitrarily around here, and if the same criteria that holds/closes any question around here were applied equally to all other questions, then 90%+ of Worldbuilding would be closed.
I realize deciding when to flag and going through the queues for Worldbuilding must be difficult because of its very nature, so I assume these holds/closes are in good faith, but they seem arbitrary nonetheless.
My opinion is that there are two ways to deal with this: relax the close trigger-fingers, or do just the opposite and be more strict but along with a more specific set of guidelines too which are applied globally.
Does anyone else notice this issue?
I think it was especially abrasive in this specific circumstance since it was done to a new 1-rep user, after the user edited the question once (shows that they are willing to work with us), and the question got a negative vote. We will get more quality members using honey than vinegar.