According to our help page, only three things are on topic.
- Theme and plugin development (unless it isn't, see exceptions list)
- Development and management best practices (unless it is too generic)
- Server configuration for WordPress (unless it is difficult or generic)
However, there is a huge list that is off-topic. In fact, the "what to ask" is pretty much defined only in terms of ill-defined negatives.
For example, we close all these questions:
- Too specific questions
- Not specific enough questions
- Questions that could apply to another CMS
- Most SQL questions
- Most code questions
- All blogging questions
What does that leave? I'm pretty sure I could make the case for almost all questions on this site as being off-topic under the first two off-topic rules - questions too specific and questions not specific enough.
These terms are too vague to be meaningful and just specific sounding enough that they can be wielded like a club. The (perhaps unintended) result is that what can and cannot be asked depends wholly on who might be online at the time the question is asked.
It is too easy to see a question, think (for any number of reasons) "I do not like this" and then close it.
The inconsistency with which I have seen questions answered or closed suggests that even those tasked with closing off-topic questions (aka the community) are not entirely sure what is on-topic either. I put it to you that questions are on-topic only if someone wants them to be.
It is often easier to ask a WordPress question that should be on-topic here on SO because it is easier than trying to figure out if it fits or not. I would not be surprised if the community is haemorrhaging experts and developers because of this lack of clarity. For that matter, I've identified enough topic areas that are now off-topic to consider proposing a second WordPress SE to group them into.
I can't be the only one picking up on the sense of frustration in this community. That frustration, I would suggest, has been created from the fact that every last one of us can have our own standards for on-topic and off-topic questions and new users have to guess what the current mood is. Long-time users are frustrated, I think, with "wrong questions" and new users are frustrated with baffling downvotes and question closures.
In conclusion, we have written ourselves into a corner and desperately need to clarify both what is and what is not on-topic. At the very least the entire "what to ask" needs to be re-written and many of the broad and sweeping terms in the "do not ask" need to be clarified extensively. In other words, I believe that our question guidance documentation is totally broken.
TL;DR: I'm flagging our own help text as too broad.