Oh boy, that sounds like trouble. Another reason to ditch Ubuntu! ZFS, BTRFS etc are awesome filesystems enabling snapshots, deduplication, self-healing and other neat stuff you want on PCs. I use them regularly. For example if you f*** up your system you can just reboot and load a prior snapshot to restore everything back to normal. ZFS is the top choice for NAS and archival where data safety is critical, as the self-healing protects your data from bitflips/bitrot (thanks to the usage of merkle trees I think). The png removal is just the loss of a bit of customization I think. But removing LUKS encryption is big! It's the defacto standard for everyone that wants to encrypt their systems completely! Like not only having an encrypted partition where you store important data, but encrypting even the boot loader so everything is secured and attacker can't gain information about what operating systems you're using etc.