Ok. But you can do rollback without using BTRFS. You could try that?
I debated the advantages of ZFS here, and people told me that ZFS is not needed and you can do rollback on Linux without any fancy filesystems.
Using lvm perhaps. I know that there is a yum plugin that takes a snapshot of the system prior to every transaction group and adds the old image path to grub.
I haven't needed to use it, however, so I don't know well it works.
Other than that, I don't know what people could've been speaking of.