No, I'm not confusing Unix with POSIX, but POSIX today superseded old Unix.
What I mean both NT and GNU enhanced and modernized their own subsystems.
Even OpenBSD is not as 'pure Unix' as Unix V7.
Even OpenBSD is not as 'pure Unix' as Unix V7.
It almost sounds like you think UNIX is an API like Win32, and that GNU is an operating system which "implements UNIX" like NT is an operating system which "implements Win32"? Are you confusing UNIX with POSIX?
GNU was made to replace UNIX, not to promote it.