My current setup is a Ubuntu laptop, with 2 external drives.

1X 2TB ext4 for data storage

1X 3TB ext4 for backup (using Crashplan commercial backup software).

My question, is if I change the first drive to btrfs or ZFS, will I gain resiliency from bitrot?

My understanding is I need 2 drives in at least a RAID 1 to get automatic healing from bitrot, but if I at least use a filesystem with check summing support then I will be able to at least restore my affected files from my Crashplan backups (which are compressed then checksummed and regularly checked for errors automatically) and I won't have the risk of my main drive corrupting my backups, because the read will FAIL if it doesn't pass the checksum.

Is my understanding correct?

Cheers,
Noah