it's not actually correct. Like, there are loads of different modules and parts that make linux system and yet we're not calling it systemd/GNOME/ostree/busybox/linux or whatever. If we're picking one thing out of many others to precise what we're actually using (because technically Android is also linux distro!), so why is it GNU coreutils specifically? It's important part of the ecosystem, but not that important. If we really wanted to use something more precise to refer to our terf of the linux world, Freedesktop Linux would be better.

The type of people to use that is the most annoying GPL fanatic who shits on every program which license isn't GPL2 or later, is a stallmite and is usually conservative to the bone. I've seen it too many times for it to NOT be true.