It has definitely NOT been dying since early 00s. The first definable moment where I think Windows started being at risk was release of iPhone and then smartph

It has definitely NOT been dying since early 00s. The first definable moment where I think Windows started being at risk was release of iPhone and then smartphones that followed it (so say 2008). But even then it wasn't yet clear that smartphones will take over the world so thoroughly and drive people from using laptops. Until that moment I would definitely project that the future will see more and more people having access to laptops. Only after it was clear people are more likely going to go with smartphones (around 2009-2010) it was reasonable to say that the market share of Windows has to start falling in favour of smartphones. And it still wasn't clear that the same will be true even within laptop/desktop market.