90
Linux has less than half of Linux’s desktop share
(www.theregister.com)
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.
I don't think you are missing anything except the creeping in scope of the term "Linux" to exclude what they don't like. Embedded Linux works with 0 GUI, and dont conforms to Freedesktop standards (obviously), yet it's ridiculous for anyone to argue that isnt Linux. Alpine Linux also do not use GNU land, yet saying it is not "Linux" is also asinine. ChromeOS imo is Linux, it's locked down Linux, but Linux nonetheless.