And not only this. Such information, if it`s public, performs two functions. First, it reports those users who have become anti-examples, in order to demonstrate what happens to those who break the rules. It`s enough to punish a couple of participants in order to intimidate everyone else (this method has been effective since the Middle Ages). Members of the forum see what the consequences of destructive, spam-shit-posting behavior are fraught with, they don`t want to be in the place of the ones who were banned. Therefore, they make causal conclusions: in order not to be banned, I need to improve the quality of my posts, I cannot spam and write nonsense.

Secondly, the openness of such information would help to understand the main reasons for the ban. As it shows a huge number of topics created in the Meta board devoted to the questions "Why was my account banned?", "What did I do wrong?" and the like, it can be concluded that most of the participants aren`t aware of the prerequisites for the ban (they are not familiar with the forum regulations, so they cannot come to the conclusion which of these rules they violated). A public list of banned users would lift the veil on the reasons for removing participants from their activities on the forum.