Here is how to get Win32 up and running: https://learn.microsoft.com/en-us/windows/win32/learnwin32/y...

It's absolutely trivial in comparison. Same thing with Xlib; < 100 lines of C code is enough for a simple app.

I have written some OpenGL applications in X11, so they did not use much of X11 besides setting up windows for the OpenGL contexts, after which the rest of the programs were written using the OpenGL API.

Those applications seemed quite simple to write in comparison with what is described in the parent article, despite doing animation in real time based on the mouse and keyboard inputs.