I am surprised to hear that you say that the difference between office 2000 and 2016 is not so big. I find that sharing files between them is huge pain and tha

I am surprised to hear that you say that the difference between office 2000 and 2016 is not so big. I find that sharing files between them is huge pain and that the UI is totally different. Have you considered LibreOffice, it is at least as fast as ms office, but can work with files from any version of ms office or other programs. It also doesn't cost money, which you didn't mention, but is a concern for most people. As for letting "your software", as the article made clear it is not yours. You keep them at the pleasure of microsoft. If they ship an update that breaks them you are screwed. If they decide that your version of office is too old for your new version of windows they can ship an update that breaks it and they are financially incentivized to do so.