OpenZFS was not previously called ZoL. It was one implementation that later merged into the OpenZFS project.
And sure, technically both FreeBSD and Ubuntu use OpenZFS codebase now, but FreeBSD has in-tree, native kernel integration, whereas Linux has DKMS modules that are separate from mainline kernel, AND FreeBSD had ZFS since 2007 (18 years) and is considered more mature, whereas Linux's stable ZFS is much newer.
Additionally, some features work better on FreeBSD, Boot-on-ZFS is more polished on FreeBSD, and there are performance differences, too.
So my original claim is fine, though illumos is probably the actual best which is technically not Solaris anymore (even though it comes from OpenSolaris)... but as with always, you need history. Follow the timeline. :P
And sure, technically both FreeBSD and Ubuntu use OpenZFS codebase now, but FreeBSD has in-tree, native kernel integration, whereas Linux has DKMS modules that are separate from mainline kernel, AND FreeBSD had ZFS since 2007 (18 years) and is considered more mature, whereas Linux's stable ZFS is much newer.
Additionally, some features work better on FreeBSD, Boot-on-ZFS is more polished on FreeBSD, and there are performance differences, too.
So my original claim is fine, though illumos is probably the actual best which is technically not Solaris anymore (even though it comes from OpenSolaris)... but as with always, you need history. Follow the timeline. :P