Yeah, one of the things this doesn't mention is that, to a certain extent, these issues are self-imposed and the GPU vendors make money from them. In particular, one of the big reasons OpenGL games are so standards-violating is that NVidia consistently refuse to enforce the specs. So software is developed against the NVidia driver's behaviour and breaks on AMD, Intel and open source drivers that enforce the specs, then people blame this on the drivers being crap and buy NVidia hardware. This was a big reason why Wine worked badly on non-Nvidia hardware for a long time.