With that recent post about chrome os not counting as a distro of linux. It does bring a good question, what is a distro of linux?
If Linux is just a kernel then android and chrome os are Linux. Bur no really considers android a distro of linux. So linux is more then a kernel.
KDE say that neon is not a distro but doesn’t really why neon is not but kubuntu is.
ChromeOS is not a GNU operating system, nor are many distributions of android. There are a lot of moving parts to an complete operating system. Even if Google uses a copylefted linux kernel and package manager Portage (GPLv2), they are still allowed to implement their own nonfree components to the OS such as a Google Chrome based desktop (Unlike with the GPLv3 which would force the entire OS to be copylefted).
Perhaps if ChromeOS were a free operating system (or at least something on par with Debian or Fedora’s committment to libre software) this argument would be trivial and we would all be happy calling it Linux, but as it stands there is still a clear distinction between ChromeOS and GNU/Linux and it would be misleading not to point them out. Corporations deserve libre software (they are important contributors), but us users deserve it too.
… KDE Neon is an extension on an Ubuntu base with the latest KDE applications. Whether you call it a linux distribution or not is based on your preferences (and the maintainers). I would call it a GNU/Linux distribution since it provides an installer and live OS image that is based around libre software.