Compression is now on by default in recent OpenZFS
Compression is now on by default in recent OpenZFS. If you have reservations, you should probably run a one-liner like this one before upgrading your OS, be it current or stable/13.
zpool list -Ho name | xargs -n 1 zfs set compression=off
If you are curious and want to know what will happen, run this one-liner.
zpool list -Ho name | xargs -n 1 echo zfs set compression=off