Ubuntu ships an outdated version that misses a lot of bugfixes. They don't seem to be interested in either backporting fixes or shipping the current stable version. Every other day some Ubuntu user hits the ZFS GitHub issues with a problem that was fixed years ago.
After hitting this in production, I will never choose Ubuntu again.
On top of the things you mentioned, it’s basically impossible to produce a working playbook that switches from Ubuntu’s garbage package to the upstream ones - systemd wedges badly about 25% of the time, and force disables the zfs units. None of the documented systemd overrides worked.
I’m enjoying devuan and openbsd at home.