I use it for a home server. Zones provides a secure way to have (on one physical machine with one physical network interface) some stuff you can only get to on the local network and some things you can get to over the public internet and some things via internet if you have the right ssh key. Each contained natively from each other. Crossbow firewall provides a nice way to contain traffic securely as well. ZFS let me set up two big external usb drives as a raid array, the resulting zvol can (iirc) have multiple filesystems for use by multiple zones although I only use it from one right now for the lan only zone. That zone shares via SMB to my network so I can use it for backups and media streaming.

I’ve been able to do almost everything in native zones. I had a bhyve zone set up to run a photo related GitHub code base that really needed Linux.

SMF is a joy to use for services and package management with pkgsrc is great. The whole thing just feels very thoughtfully put together.

You can probably achieve all this on Linux with docker and the right iptables (or whatever succeeded it) config I imagine? But on smartos I am using facilities that are integrated deeply into the os going back like 20 years now. I also just prefer the old sun stuff.