Some things I like about FreeBSD in particular:

- high quality docs, especially for development. In my experience manpages are to a higher standard than Linux, especially for syscalls and the like - `make install` - you can build userland, including libc, and the kernel in a couple of commands and then reboot into your new system (or fire up a VM). this is extremely hard to do on most Linux distributions. - a smaller community where it's perhaps a bit easier to meet people and contribute. I remember going to the AUUGN conferences and the *BSD folks there were always friendly

All of that said, while I did use FreeBSD as my desktop OS at various times in the late 90s and 2000s, I haven't for years. Although I am now curious to see if I can fire it up on a Pi or something like that :)