Do not use btrfs; it's pure shit.
Today I was hit by this 2014 issue with my 2018 kernel and userland: http://marc.merlins.org/perso/btrfs/post_2014-05-04_Fixing-Btrfs-Filesystem-Full-Problems.html
Suddenly, I started getting ENOSPC errors in the middle of a package upgrade, and the system became unbootable.
df reported the partition 68% full, and btrfsck didn't find any issues. It took me *hours* to discover 'btrfs filesystem balance' and convince it to work on a full filesystem.
This isn't even the first time I have to recover a btrfs partition. Enough.