Bad idea: network storage services should have an option to expose their storage space as a block device instead of a filesystem 
(Easily doable if homebrewing your NAS but I haven't seen any of readymade software that does that, be it self-hosted or cloud-based)
Follow
Like, everything would be so nice like that
Want encryption? Just layer a LUKS or VeraCrypt device over it!
Want to store a lot of data compactly? Just layer a ZFS/btrfs/NTFS with transparent compression, no more manually zipping files!
Use any filesystem you want, with all the features you want!
etc.
Though I dunno how would that work if the device is mounted on multiple machines 
@koakuma https://github.com/archiecobbs/s3backer