There is a option similar to a block available to mods. (well, really just to me). I only do it in rare cases but it will monitor and delete comments if two users leave a message on each other's saves.

If a user is causing problems we want to be aware of it. If I do ever add blocking, it would be something closer to this bidirectional comment ban, rather than completely blocking interactions. But I don't want it to be abused, for example for harassment or for silencing all negative comments. That's why it's a jacobot-only tool right now.