Linux by default does mean Linux kernel, but in my reply I didn't cared about that either. When all know what is meant, that is fine in my opinion.

I think it is important to have GNU/Linux in mind, because there are OSs that don't use glibc and work totally different, so none of your complaints apply. But yes, most people think of GNU/Linux, when you tell them about Linux.

It is also relevant to consider that there is no OS called GNU/Linux. The OSs are called Debian, Arch, OpenSuSE, Fedora, ... . It is fine for different OS to have differently working runtime linkers and installation methods, but some people act surprised when they find out ignoring that doesn't work.