So you've apparently just proven that no discrimination exists in the business world. South Africa's native population was just too stupid to work any job, until Nelson Mandela was freed, instantly improving their skills to make them eligible for employment.

Nobody would forgo a good bread, so Germans writing "Germans don't buy from jews" on bakery windows were just making the case that the bread had, within a few years, become intolerable. Hollywood studios stopped hiring communists because communists just aren't very funny. etc...