This question didn't fall under any off-topic reason, so it sat and lingered for almost a year and a half. Finally after months of asking "Can you please provide more details?" and no response, it was finally closed. The sheer length of time and lack of an actual reason to close it was frustrating.
I don't quite grok this reasoning. First, the descriptive assumption that the "lack of an actual close reason" seems to fail even a cursory review of the question.
It's marked "Too Broad", and in the description of too broad, it says to "add details to narrow down the answer set":
I'll elaborate a bit more below...
Custom close reasons should be site-specific
Is there a way to add a whole new reason for putting a question temporarily On Hold (similar to how unclear what you're asking works) under Not enough details?
We don't need another close reason for not enough details; the combination of your comment and the aforementioned close banner seems perfectly adequate for this task. Furthermore, Stack Exchange wants us to limit custom close reasons to site-specific issues. In case it's not already obvious, not enough details is perhaps the most common problem across the Stack Exchange network (assuming the question was on-topic to begin with).
If you want to give people general direction on what to document, we already have a huge post explaining what details people should add. BTW, we could use some good examples of how to document all those details; perhaps someone could start with "How to build a good network diagram" meta post.
Unfortunate realities
The sad reality is this... A lot of people just don't bother adding details. It doesn't seem to matter how many times we ask them. People also abandon questions.
In my opinion, this particular problem most likely comes down to not caring to update the question. We just need to close stuff that isn't asked well enough to answer; it's boringly-normal site maintenance.
Close Dialogue comparison
Finally, I'd point out that our cousin-site (ServerFault) spent quite a bit of time and energy tweaking custom close reasons (this is one example). Guess what SF's basic close dialogue looks like today...
ServerFault Close Dialogue
Now compare that to ours...
NetworkEngineering Close Dialogue
The differences in the Close Dialogue are... close to zero.
What is interesting is to compare how they tweaked their custom off-topic reasons...
ServerFault Off-Topic Reasons
Our off-topic reasons have not been tweaked yet; I'm personally undecided about whether there is a case to do so.