I know that it really sucks that this close reason is listed under "off topic"... There's a proposal on MSE to change the close voting system to allow more custom close reasons outside of the "off topic" category and I (and Nathan Tuggy) have both written well-received answers there but this feature request is ignored.
I've recently seen (unscientifically) a bit of an uptick in the generic close reason being used and it may be because people don't realize we have the custom one.... so
Please note, the generic "unclear what your asking" close reason does not link to our purpose written help info and is not as useful, as it only links to the generic "how to ask" page:
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.
In contrast, the custom reason links to our helpful meta topics on how to write better questions:
This question should include more details than have been provided here. Please edit to add the research you have done in your efforts to answer the question, or provide more context. See: Details, Please.
While there certainly are cases where the "unclear what your asking" close reason applies (see Colleen's comment), many questions closed this way would be better served with the custom reason.