You replied exactly to my question. The idea behind exaequOS is not reinventing CSS at all but to support “Classic” apps (terminal, graphic toolkit, OpenGL) and html/css apps
Oh absolutely! Sorry, that comment wasn't directed at exaequOS, but discussing some older human interface guidelines and older UX standards. Just pointing out that interfaces have evolved since then.
But that's not the point of exaequOS and that's okay!
You replied exactly to my question. The idea behind exaequOS is not reinventing CSS at all but to support “Classic” apps (terminal, graphic toolkit, OpenGL) and html/css apps