Most likely a side effect related to Windows team finally giving some C# love, instead of COM and C++, given the comparisons between C# 16 with Rust and Swift in a few article sections.
In terms of XAML UI, C++/WinRT struggles. When it was released, C++ just lacked good reflection methods, and many practices that were easily achieved in C#, such as MVVM, data bindings, were difficult to migrate. I think this prevented C++ from re-entering modern Windows development practices.
