If you look at Linux distributions, GNU ist just a relatively small part if you look at lines of code. And of that most is GCC and GDB:
>GNU is not an operating system
Could you please elaborate on this position?
>but a collection of mostly commandline tools.
"Mostly" being the keyword, it also contains multiple implementations of different programming languages as well as their standard libraries, a kernel as well as a package manager. Also in the commandline tools it includes most (if not all) of the tools that are required by POSIX.
> If you look at Linux distributions, GNU ist just a relatively small part if you look at lines of code
I am unsure how this is relevant. In fact, I would argue that this is to be expected, especially when considering that the link checked everything in the main repository.
> Could you please elaborate on this position?
GNU is not an operating system, but some small projects that are used as minor components of Linux distributions
> GNU HURD and GNU MACH
Nobody uses them. They are as relevant as the Windows Services for UNIX
I think that I will have to disagree with that. Instead I would argue that it is actually like saying that Busybox + Linux is an operating system as defined by POSIX or like saying that if Busybox had its own kernel it would be its own operating system as defined by POSIX.
> GNU is not an operating system, but some small projects that are used as minor components of Linux distributions
In my previous post I mentioned some of the components that allow GNU to be used as a modern and POSIX compatible OS. It just so happens that most Bash distributions instead of using GNU Mach use Linux as their kernel.
> as minor components of Linux distributions
I think that calling them as "minor components" is quite a bold claim.
> Nobody uses them
Does not change the fact that they are both part of the GNU project. Nor does it change the fact that one can use them in order to run the GNU operating system without 3rd party software.
Hell, neither does GNU/Linux for that matter (it's not technically POSIX) but busybox is really way too minimalistic to be considered an OS.
In the time frame they are talking about, 1993-1994, almost nobody was using Linux commercially (except tjhe distros selling it). Even after that, Linux was fairly immature. If BSD was going to be a real contender, it still had a sizable lead. That it didn't win in the end leads me to believe other factors were more important, such as the license (which the article you linked also notes).
The BSD license is more permissive and appealing to a lot of organizations, but the requirement of the GPL to give back ultimately lead to a virtuous cycle where companies moved portions of their code in-kernel, because out of kernel is more problematic if it's also not proprietary.