I’ve been using sshfs for years to share files between various Linux systems and a between a Linux fileserver and a MAC – it has worked ok – definitely not perfect, but easy to set up. Just re-installed my macbook today (kids have been using it over the past years and disk is full, so easiest to just start over). Looking into the sshfs stuff for MAC – does not seem very well supported. So interested what others use.
One of the challenges with a fileserver is managing users, groups, permissions, etc.
I currently use Samba, primarily because it’s really easy to setup and we have a few Windows PCs in the house.
For file synchronization, I’ve heavily used https://syncthing.net, and it has worked very well. Syncthing is a Go program that runs on Linux, Windows, Android, etc. This is how I sync my phone’s photos with our home rPi file server.