I left out FreeBSD from that comment, which has its own set of innovations: Capsicum (capability-based security framework), Jails (OS-level virtualization/containerization which predates Docker by over a decade), MAC Framework (Mandatory Access Control for fine-grained security policies), GEOM (modular disk I/O framework), Linuxulator (Linux binary compatibility layer), ZFS (FreeBSD has arguably the best ZFS implementation outside of Solaris), bhyve (type-2 hypervisor), and so forth.
Userland tools include iocage/bastille (jail managers), poudriere (package building), jemalloc (default allocator which focuses on fragmentation avoidance and scalability) among many others.
Each BSD really does have its own character. FreeBSD leans toward performance and production use, OpenBSD toward security and correctness, NetBSD toward portability and clean design, DragonflyBSD toward alternative SMP approaches!
(illumos/OpenIndiana is quite interesting, too (see DTrace, Doors IPC, Zones, SMF, Contracts, Event Ports, RBAC)).
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
I left out FreeBSD from that comment, which has its own set of innovations: Capsicum (capability-based security framework), Jails (OS-level virtualization/containerization which predates Docker by over a decade), MAC Framework (Mandatory Access Control for fine-grained security policies), GEOM (modular disk I/O framework), Linuxulator (Linux binary compatibility layer), ZFS (FreeBSD has arguably the best ZFS implementation outside of Solaris), bhyve (type-2 hypervisor), and so forth.
Userland tools include iocage/bastille (jail managers), poudriere (package building), jemalloc (default allocator which focuses on fragmentation avoidance and scalability) among many others.
Each BSD really does have its own character. FreeBSD leans toward performance and production use, OpenBSD toward security and correctness, NetBSD toward portability and clean design, DragonflyBSD toward alternative SMP approaches!
(illumos/OpenIndiana is quite interesting, too (see DTrace, Doors IPC, Zones, SMF, Contracts, Event Ports, RBAC)).