I'm still using Win32 (via WTL) to write a developer focused application, but I know that someday I will need to switch to Qt, dear ImGui, or develop my own UI abstraction layer.
The biggest disappointment has been that all new OS features require a new runtime and are not accessible from just pure Win32 any more. Heck the pipeline for developing UWP/WinUI3 apps requires extra steps to register and install the application just to run it inside a debugger.