[magnawave]

As commented already, this is actually incorrect. RAID cannot and will not detect data errors unless the drive itself report the errors and issues the "I can't retrieve this data" call back to the raid controller. If it lies, RAID is fat dumb and happy. Sadly, drives lie all the time.

Now in reality in big enterprise SAN arrays, the vendors usually add checksum blocks onto the underlying disk (aka larger sectors in the Clariion, or checksums into the filesystem on NetApp) OR use special certified firmware on the drives that make sure the drives never lie themselves! So largely if you are on a big enterprise SAN, you probably don't seriously need to worry about bit rot.

But outside of that space, most PCI card RAID controllers, and I suspect at least a few "enterprise lite" arrays, probably don't do checksum calculations. So BTRFS and ZFS provide notable value. (and definitely on raw drives)