Does it belong to employment discrimination that civil positions such as administrative back office do not recruit men?

In general enterprises, especially private enterprises, the phenomenon you mentioned is quite common, and civil positions such as administrative back office are generally only for women. However, in some large state-owned enterprises, there are also men in civilian positions in government agencies, enterprises and institutions, but if you want to work in these units, you need to pass the exam. The reason why enterprises do this is because these positions are more replaceable, while women are generally less motivated and want to find a relaxed and stable job.