Those are not disadvantaged anymore. These are of course exceptional cases i.e. poor white kids, rich black kids, but they are only insignificant if we consider society at large.
We also tend to make a mistake of assuming that society is inherently fair and would therefore apply "meritocracy" at all times. The fact is we are raised with prejudice and sterotypes (more so in SA, owing to our past). A white person is more than likely to hire another white person unless there is none available. Same goes for a black person. It's the whole language/cultural upbringing phenomenon. We all tend to put more trust on things that are more familiar to ourselvels. One english speaking white forumite has mentioned that it was hard to get a job at telkom/eskom/SABC unless one was afrikaans. The reality in SA is that the employer is white (excluding government).
And also don't make it seem like every job in SA is AA, not even in governement (otherwise Elec Erwin wouldn't have a job. LOL)