While I do not disagree with Jim(I guess I do disagree) I do like a proper NAS setup and think it's easier for most users. Their OS is usually just a customized Linux distro with EXT4+RAID/LVM filesystem.
I have a 4-slot QNAP currently with 3x16TB in RAID5:
- easy to setup
- easy to add disks to enlarge the storage pool, or replace disks with larger disks
- web interface for configuration and file management
- very low maintenance, just the occasional OS upgrade which can be automated (I prefer manual)
- low power consumption (if you can get your disks to sleep properly), low noise, low temperature CPU
- Network Recycle Bin! Seriously, I don't know why this is not standard in Windows (VSS is not the same thing). It saves my ass so many times.
- multiple backup paths - can backup to a number of cloud services, to local USB/Network devices, or rsync with another NAS/server anywhere
- optional functionality with
app store: I use it for FTP Server, VPN Server, DNS Proxy, DynDns Updater and a couple other functions
- many multimedia capabilities which I don't use: Plex/Roon/Twonky servers, Photo/Music/Video station, DVR for IP webcams, etc
- advanced features such as Snapshots, Thin volumes, Domain Server, SQL Database, Apple Time Machine target, etc
- many models can also run VMs and Containers
A Windows/Linux server can have all that and much more. It can be more flexible. However, the maintenance needs are
much higher and you need to figure out how to install/configure each one of those items.