Perhaps those affected could appeal or complain to Agoracom itself. We know the "system" tracks information (e.g. whether a specific user has recommended a specific post, so itwouldn't surprise if each post or post deletion is tracked by a logging system. Agoracom may be able to identify whether one or more people on this PTSC board have a record of exceeding the average number of deletions.
I must agree that the threats of deleting posts which are not in accord with the delete-empowered reader's preferences reek of censorship at its worst.
Maybe there is a configurable option whereby Agoracom could elevate the level at which the delete privilege is activated.