Glad those with ZFS 0.8 are back up and running with the Focal HWE kernel.
Those tracking the latest/stable channel will always get the latest feature release of LXD, and over time (but especially at the boundary of a new LTS release) the minimum requirements for LXD will change.
With the LXD 5.21.0 LTS release as planned, we have now changed the default snap track from latest to 5.21. This is to ensure that those installing LXD by way of just doing snap install lxd wouldn’t end up on the latest/stable channel but would instead get the latest LTS channel (now set to 5.21/stable).
We won’t remove support for specific ZFS versions during the lifecycle of an LTS release, so those following a particular LTS track will need to consciously refresh to a different track (i.e latest/stable or a future LTS track) to get new features.