Adding realms backups stored on the server was a great idea, but it wasn't very well-implemented. I recently had to undo some substantial griefing-by-wither in my realm, and was surprised to find out that the vast majority of the long list of backups was from the last 24 hours.
The kids who spawned the wither at our nether hub waited two days to tell anyone, so your backups were useless. Fortunately, I've been making my own backups every week and was able to use one of those.
Even now, my realm has 19 backups for the last 24 hours, and only a handful of older backups, the most recent of which is from June 3rd. Do we really need that many backups from the last 24 hours? Who micromanages their realms to this extent that isn't, in essence, trying to cheat the system? If I hadn't been able to use my own backup, I would have been stuck with massive griefing damage, since going all the way back to June 3rd would have undone nearly everything in the realm.
Can't we have maybe a backup every few hours for the last 24 (maybe 8 for the day) and the rest at maybe one a day for the past week, one a week for a few months, and once a month for older realms? It would use just as much memory space, maybe a lot less in most cases, and be a lot more useful for everyone.