@sendpaws @feld

BSD? Do you want a storage appliance with support. You go to iX Systems or Oracle. One uses primarily FreeBSD, the other bought the company that built the FS in the first place.
Other users: Netflix, literally every enterprise firewall that doesn't use purpose built hardware for high-speed throughput.

Illumos: Nobody, same with all the other operating systems made to replace discontinued proprietary ones (ArcaOS and alike)