And if the ai would communicate with these toxic shadowbanned people in such a way they become aware of their rudeness or mistakes on the forum? If AI creates a feedback loop then it's all right?
If AI could help people to bring their point or grievance across in a clear manner, this would be the opposite of a shadow ban. This can be done transparent, in Form of a suggestion.
E.g to write penis as p.e.n.i.s. to make clear that proton enhanced neutron induction spectroscopy is abbreviated here, might be helpful to some.
AI can create a feedback loop ethically, if it makes itself know as an AI or automated system or Eliza 2.0. The user can choose to just opt out or mash on his keyboard as he pleases, as we do since 1964.
That is all ethical, but deceiving users and trapping them definitely isn't.