Probably the closest thing that already exists is just running Cockpit[1]. 45Drives even maintains some helpful storage and file sharing plugins for it[2], though some of those are only compatible with x86 for now.
Cockpit hasn't really improved in a while, though, and although I greatly appreciate 45Drives' committment to it, last time I tried to install their stuff I had a lot of issues with deprecated dependencies...
So I just went "raw" smbd and never looked back, but then again I've been running Samba for almost two decades now and configuring it is almost second nature to me (I started doing it as an alternative to Novell/IPX, and later to replace AppleTalk...)
In practice, I've found that worked well because I very seldom had to do any changes to a file server once it was set up (adding shares was mostly a matter of cloning configs, and what minimal user setup there needed to be done in the enterprise was deferred to SAMBA/CIFS glue).
Quite true; raw configuration isn't as flashy so you can't make glitzy videos or blog posts about it (well, outside of the HNsphere at least).
But that's how 99% of the services I run are set up, just a bunch of configuration files managed by Ansible.
The only servers I run in production with a UI are two NASes at home, and the only reason for that is I want to run off the shelf units so I never have to think about them, since my wife and kids rely on them for Jellyfin and file storage.
I would imagine it's because it makes for a lot more fun support possibilities when all the underlying stuff in the stack (kernel, ZFS, Docker, Python, etc. etc.) is subject to the whims of the end user. When you ship the entire OS yourself you can be more certain about the versions of all the kernel+userland stuff and therefore the interactions between them all.
