I was looking at this question about a 17-year-old Ph.D. student in astrophysics, and I was struck by the potential for identifying this student (if it's a real scenario, which I don't for a second believe, but that's another topic). The number of current 17-year-old astrophysics Ph.D. students is minuscule, which makes this description extraordinarily specific. It may not uniquely identify the student, but it probably comes close. What makes it problematic is that the question was supposedly posted by the student's advisor, not the student, so there's no reason to think the student would be OK with being publicly identified.
If the classmates of such a student notice this question, they will surely wonder whether it's the same student, which could be awkward. Furthermore, one particular 17-year-old astrophysics Ph.D. student has recently been in the news for allegations of plagiarism, which makes this question sound like a sly reference to that case.
Do we have a formal policy on this issue? How should it be handled?
I'd propose deleting questions that include this level of identifying detail for third parties, to avoid embarrassing the people involved. (We could make an exception for cases in which the identifying detail is crucial for the question and no awkward or embarrassing material is revealed beyond what has already been widely circulated.)
There are at least two risks here:
Accidentally identifying third parties, for example if an advisor posts a question about a foolish or eccentric thing that an identifiable student has done.
Deliberately posting misinformation designed to embarrass someone by making it appear that information is leaking about an identifiable third party.
Either way, I find it problematic. (By contrast, people are of course welcome to post whatever information they feel is appropriate about themselves.)