@hypolite This "mutual only" would only work if all systems established it. Due to the nature of AP, commenters will distribute their comment on their own. This is something that the "commented on" account can't control.

Means: We can check if there is an commonly agreed way of "you are not allowed to comment here" and we can implement it. But I would only implement the other way when the support is given by most systems. (Same occurs to "comments closed")