Comment by c-smile

It is not. Not to that extent at least.

I am developing Sciter[1] engine that works on all desktops: Windows, MacOS, Linux (3 distinct backends: pure X11, pure Wayland and GTK4).

Among all those, Windows API is still the most consistent and stable.

Whole of Windows functionality can still be accessed by plain C. For some things (COM) is better to use C++ but C works too.

Just in case: I am in this business for 20+ years.

[1] sciter.com