Hard to say what's native in Windows anymore. I imagine Win32 APIs and more recently Windows App SDK?

The most supported UI frameworks from MS for Windows are WPF and WinUI 3. UWP is dead and WinForms (even though closest to something native to Windows) is probably going to end up in the land of forgotten (sorry nostalgic Windows devs, you have to face it eventually).

A "mess" is an understatement when the people who themselves develop Windows desktop apps have trouble explaining the landscape.