Not quite true IMHO. One of best features of ZFS is checksumming to ensure data integrity, where errors can be corrected if you have enough redundancy.

You certainly lose this feature with single disks, but you're not necessarily worse off than any other file system.

What ZFS gives you on a single disk is very convenient snapshots and very convenient (incremental) streaming of those snapshots to another system (via either a push or pull mechanism). Doing this with other file systems generally entail a lot more work and much less efficiency. btrfs can do it, but if you're using ext4, then you'll probably use rsync which has to walk the file tree to find changed files.

Also with ZFS and snapshots you can turn them into clones: writable copies. This allow boot environments were updates/upgrades can be done, and if things do not work out, you can boot back to the original setup:

* https://mwl.io/archives/2363

* https://vermaden.wordpress.com/2021/02/23/upgrade-freebsd-wi...