I know you are trolling, but there you go.

https://en.wikipedia.org/wiki/History_of_Unix

https://en.wikipedia.org/wiki/Unix

https://en.wikipedia.org/wiki/POSIX

http://www.opengroup.org/standards/unix

His point is probably UNIX didn't won -- Linux did.

Linux is non-certified copy of UNIX, without POSIX it wouldn't matter in the marketplace, ergo UNIX won.

As you can see in the wild, nobody really cares about UNIX certification. Ergo, UNIX didn't win.

The fact is that the Linux kernel without the APIs copied from POSIX/UNIX and the userspace copied from UNIX is useless on the server space.

Of course we can play semantic games about the use of UNIX word, and GNU/Linux not sharing any code from either BSD or AT&T linage, it doesn't make it any less UNIX.

Had Linux not copied UNIX, and provided a playground for UNIX vendors kind of outsource their development costs, it would have turned out to yet another hobby OS.

NT had POSIX subsystem too.

What Linux (and NT POSIX to certain degree) allowed, was to move the existing investment in software from hodge-podge of mutually incompatible, but expensive UNIX systems, to somewhere else.

NT isn't a copy of UNIX, just because it had support for the first edition of POSIX, it goes beyond than that.

Starting by wanting to copy Minix, an educational OS that copied UNIX, getting the GNU tools on board (which goal was to copy UNIX), kernel architecture, device drivers subsystems, userland, culture, ....

My old stack of Linux Journal editions at home are pretty clear what the ongoing story was.

If NT was a copy of anything, it was VMS given Dave Cutler's contribution to its design.