Even how grades are generated, typically at the complete discretion of the professor, is all over the map. Some weight, some curve, some give extra credit, some inflate, some put outcomes over numeric values, some base evaluation off of a single exam, others weigh participation as heavily as course outcomes, and on and on. In other words, grades are different to almost everyone. Yet we all seem to buy into the representative nature of grading, ignoring the elephant in the room.
Most companies never ask for a transcript, and for the few who do, it is only for those seeking their first job out of college. (Working inside education may be an exception.) After that, grades mean almost nothing. What companies instead seek are the things that grades, which become so easily gamed by both students and teachers, can diminish. After all, if the grade is all that matters, then trying new things and failing (actually promoting learning) will be negated. Teaching to a test, jamming information into short-term memory only to be lost a few weeks later will be the norm. Critical thinking will be lost. Problem solving based on context will be supplanted with algorithm practice absent of context.