Is in-kernel ZFS mature enough to be used as a daily driver on a GNU/Linux laptop NVMe (and generally without a complete system backup to grab when it shits its pants) with reflink, continuous-ish CoW snapshots and data deduplication?
XFS turned out to be really nice and good enough to deploy by default, but it's lacking proper snapshot provisions (the idea to add some LVM thin awareness for the free space accounting didn't took off it seems: https://marc.info/?l=linux-xfs&m=150900682026621&w=2), and BTRFS is still too buggy for my taste after a decade of development.