As a non-gamer, you might not fully grasp how entrenched Windows is for game development, distribution, content creation and modding. This is significant and reporting on it is good stuff, even if it's outside of your niche.
This is not an argument in good faith. Nintendo is a company that primarily makes hardware to sell its own games. The Wii is not a general computing device and we never expected it to do that.
Linux claims to be a general computing operating system, but had historically not prioritized gaming (or UI…). This has changed and the article notes as much. Windows OS is used for a benchmark because it is still the gold standard, and the OS that most games are intended to be executed with.
Why are you holding computing to the same standard?
I'm curious as a non-gamer. The article seems to be entirely about Windows gaming.