Moderators cannot silence users from forums, we can ask support to issue a permanent forum ban though.
The current situation with this rule is that is agreed with developers, but they never bothered to update the Terms Of Use. They have issued no guidelines of how we are meant to enforce, or whether we even should. I believe that the Terms Of Use were meant to be reviewed in December, but this never took place. I'm not sure if the TOU is still the version with a different game than pimd featured throughout.
So, there is nothing moderators can do. We can't silence users from forums, we can't silence for it, and we can't request a forum ban for it. I have repeatedly asked members of the support team for guidance on this issue but none was provided. I think that the developer who introduced the 'Get off my thread' rule, did so without consulting the support team. However, he has now left A Thinking Ape. The only way this rule would apply is if the user is breaking the Terms Of Use on a thread, then the OP can request that they cease posting.