Earlier quoted context omitted.
Long story short, that you kind have to assemble from blog posts, forum comments, between the lines articles and so on. Longhorn was to be built on top of .NET and there were lots of issues, regarding performance, stability and what not. Apparently it was more a thing of WinDev (owner of Windows and C++) and DevTools (owner of VS and .NET) each pulling to their side instead of collaborating. As proven later by Singul…
I think Sinofsky was still in Office when this was happening. He comes into the picture with Windows 8 since Microsoft wanted Windows to be as successful as Office had become. Jim Allchin ( https://en.wikipedia.org/wiki/Jim_Allchin ) was in charge at the time of Vista. Office had stuck with regular the regular Windows platform and were focusing on UI and getting into a regular release rhythm under Sinofsky. People fo…
Undoubtedly there were multiple issues at play there.
However having been part of such "rebuilt the world" projects, I do believe politics also played an important role, as many signs that came into the outside world feel similar.