with opengl, you can go on a website from 2002 and spend a couple hours on a tutorial making a game where a texture-mapped cube moves around a heightmap grid shooting lines at other cubes. this is a severe issue fundamental to the API itself, as it leads to inexperienced people writing graphics code. vulkan fixes this, by filtering out such people, so their contributions are discarded, and only graphics produced by professionals and serious dedicated autodidacts will ever reach the screen