I did a search for communities with “history” in the name. It came back with !history@links.hackliberty.org even though that instance has been down for over a year. If I did not already know of that instance going down, I would just post there expecting my post to be seen, because there is no indicator of when the server was last up.
That wouldn’t exactly hit the mark because a ghost community /can/ be active. The problem is that if you have:
You can see the local copy of nodeA/someCommunity@originalNode if you are on nodeA. But you don’t know it is orphaned and you are in a bubble. People on nodeB can see posts in nodeB/someCommunity@originalNode, but not nodeA/someCommunity@originalNode. There is no signal that you have been cut off, and that your post will only have a local audience.
We already have transparency of activity, but not transparency of scope and reach.
I would even say adding the transparency is just a start. The real bug here is that the fedi has not figured out that nodeA and nodeB need to sync with each other regardless of the parent.