I am experiencing the exact same issue. My Realm is fully playable and active, but every attempt to download the world fails. It used to get stuck on "Starting Download", but after swapping Realm slots and restoring backups, it now fails instantly with Error 404. This happens on both PC and console, and all backups are affected (old and new). The issue started around 5 days ago.
NATAN SCHNEIDER
I am experiencing the exact same issue. My Realm is fully playable and active, but every attempt to download the world fails. It used to get stuck on "Starting Download", but after swapping Realm slots and restoring backups, it now fails instantly with Error 404. This happens on both PC and console, and all backups are affected (old and new). The issue started around 5 days ago.