Politics, .NET has always been part of DevTools business unit, while C++ and Windows were under WinDev roof.
Longhorn's goals was to rebuild Windows on top of .NET, naturally there were performance issues with the state of .NET 2.0 capabilities.
However instead of working together , while improving the whole stack (languages and runtime) to make it possible, like Google teams have later done with Android and ChromeOS, they just deemed it impossible and started pushing for a reboot.
When Sinfosky of the Office team took charge (another C++ holdout at MS), they picked up all the Longhorn's ideas redoing them in COM.
It is no surprise how WinRT turned out to be COM 2.0 with him in charge of Windows 8.
Longhorn's goals was to rebuild Windows on top of .NET, naturally there were performance issues with the state of .NET 2.0 capabilities.
However instead of working together , while improving the whole stack (languages and runtime) to make it possible, like Google teams have later done with Android and ChromeOS, they just deemed it impossible and started pushing for a reboot.
When Sinfosky of the Office team took charge (another C++ holdout at MS), they picked up all the Longhorn's ideas redoing them in COM.
It is no surprise how WinRT turned out to be COM 2.0 with him in charge of Windows 8.
https://hackernoon.com/what-really-happened-with-vista-4ca7f...
"Turning to the past to power Windows’ future: An in-depth look at WinRT"
https://arstechnica.com/features/2012/10/windows-8-and-winrt...