Hi!
to me that this could easily be used as a shaming and blaming list. If the block is over and the person wants to change their behavior, it might be hard for them to start with a clean sheet if we keep a backlog public of everyone. I'd see it not only as a privacy issue for the people reporting, but also the reported.
You have a good point here. Maybe it should not be permanent, but should expire after the ban is lifted. I can see how that could be better (though nothing that was ever public is completely forgotten, but still not carrying it around in our spaces might be good). So I'd say public record while the ban is active is a must, but after that expunging the record is fine.