The problem is that all the user facing stuff in macOS isn’t BSD. It’s Apples proprietary APIs. So while macOS was originally and technically based on BSD, almost none of that is exposed to their users.
So they’re technically correct that macOS / Next was based on BSD. But also completely wrong to recommend macOS as a comparison to OpenBSD.
BSD stuff has a complicated history due to the lawsuits in the 1990s.
NetBSD and FreeBSD were based on 386BSD. OpenBSD was a fork of NetBSD by one of the NetBSD founders (Theo deRaadt)...
Also OpenStep is an API rather than an OS. So macOS contains both NextStep and OpenStep code.
AFAIK there isn’t any BSD code in Windows however the original TCP/IP stack in Windows was a port from BSD. But we are talking about the early 90s here and it’s long since been rewritten by Microsoft (or so they say, but I have no reason to disbelieve Microsoft)
Microsoft did leverage BSD code for common network utilities (ping, tracert, ftp, etc.), which still exist in Windows today, although Microsoft's preference is to leverage the "better" equivalent PowerShell cmdlets where available.
[0] https://en.wikipedia.org/wiki/Spider_Systems
[1] https://web.archive.org/web/20151229084950/http://www.kuro5h...
EDIT: If you want to hunt for BSD code, try taking a look at NT4[2].
[2] https://github.com/lianthony/NT4.0/tree/master/private/ntos/...
https://en.wikipedia.org/wiki/Windows_Vista_networking_techn...
After NeXTSTEP 3.3 there was OPENSTEP 4.0.
OPENSTEP 4.2 is the last operating system release prior to Rhapsody.
Yes it’s confusing.
Considering how obsessed with UX that Jobs was, I don’t get how he thought the naming conventions were a good idea.
NeXT looks good in the logo, and they spent $100,000 on it.
FWIW, I like it but it is confusing and made harder by the fact they also didn’t stick to their own conventions much of the time.