Staff don't remove or moderate feedback.
Are you sure? I have seen a lot of people have been removed from the default trust list due their (left) negative trusts and you are saying that the trust system is not moderated (I think it is no-sense) but I accept your opinion.
It's not the same removing someone from the default trust list than deleting a feedback left by someone. If somebody is removed his feedback is still available whenever he left it, it's just not trusted by default.
Besides anyone from default trust level 1 can add or remove users (level 2). That's how the system works and that's not moderation.
Some people have been removed from level one and that's more difficult to happen but still it's not the same as moderating the trust system.