Some people, while having not fully understood the question (or don't really know about the topic) tend to try to close such questions and move them to another site.
As you can see, no one really gave a comment or started a discussion about whether it fits better on another site.
It feels annoying to put a disclaimer into my question that I want it to stay on Stack Overflow; in this case because I want to have the problem analysed in a code-related way. By asking it on Stack Overflow, I am already implying that I want to get it answered code-related, so why do I need to specially say that?
In this case there was a discussion and it showed that people had different opinions on that. The problem was that the people who agreed with me that this is a programming-related question couldn't unvote the close-votes. And probably not all of them had an account on Server Fault or not all of them checked back once it was moved, so it stayed there. (In the end, I got a few answers (which are all programming-related...) so I don't care any more about this question and maybe it really was a corner case, but it demonstrates the problematic.)