It is a security hazard because if someone who was rightly banned can see the evidence then they can figure a way around it.
I have been banned for Macroing in the past. If I was given the evidence as to how they received the information that I was macroing then I could find my way around their detection process.
It's the same with other MMOs like RuneScape. If I am banned for botting, they won't tell me how they figured I was. If I knew how they figured it out then I could work my way around it.
This is why a hacking/cheating ban is harder to "falsely" appeal (not saying you actually cheated/hacked) than a simple ban for screaming "UNIXMAD LIKES BREAD AND *** * * * * **** *** * " in Graal City.