That’s still true, but performance has changed a lot since Jim Salter wrote that. There was a time When 2x mirrored vdevs (the equivalent to raid 10) would have been preferable to raidz2, but performance of both ZFS and disks themselves has improved enough that there wouldn’t be much of a difference in performance between these two in a home lab.

Personally, I agree with you in that mirrors are preferable, mostly because I don’t really need high availability as much as I want an easier time restoring if a disk fails.