"Going native" meant salvaging Vista's low performance by rewriting everything in C++ that was written in .NET -- .NET was the "wave" here, but it's also the culprit for Vista eating memory like cheap sushi.
Yet, the replacement of Win32 API model is with everything being written in the original design of .NET, with AOT native compilation and classes being COM objects.
What killed Vista was politics between OSDev and DevTools units.
What killed Vista was politics between OSDev and DevTools units.