I've lost track of the amount of times I accidentally deleted a file I shouldn't have or messed up a git project in a way it'd have taken ages to untangle, said oops, remembered I have hourly snapper snapshots set up and just copied the previous state over. It's been a massive time- and occasionally lifesaver for me.

Rolling back or cloning the snapshot lets you get back deleted files, or reverting a bad update or config change...

The snapshot is also a point in time to derive backups from, and usually costs nothing to make, as opposed to making a dd image of the disk, or tarballing everything, etc.

Whether you think you need those is debatable, but it's quick and easy enough, works for me.

One thing the sibling did not mention is you can use btrfs send/receive to create dead easy, fast, and simple to restore incremental backups.