Indeed, nowadays I feel myself a fool for having advocated for WinRT, it was one of the reasons why I returned back to Web and distributed systems, after spending four years back in Windows GUI development land.
And my advice now is for .NET devs, stay with Windows Forms or WPF, depending on which approach they favour.
For C++, I suggest the aging MFC if it has to be on the Visual Studio (still better out of the box experience than WinUI 3.0 for C++, and C++/WinRT is in maintenance anyway), but really Qt or C++ Builder are much better option.