While I am sure I missed some stuff, I know there has been some talk on what would rclone have to do to make Borg able to read and write to an rclone mount. I saw in the changelog:
- Implement lock ordering between File and Dir to eliminate deadlocks (Nick Craig-Wood)
and I seem to recall there was an issue with Borg related to locks. Does this address that? Anything else that may make it work?