Your sample size of five elite companies can't be taken as a serious attempt to describe the actual experience of black CS grads applying for jobs.
So that's 1.5% of all engineers. And that's being very generous. The real number is surely below 1%. No surprise that the most desirable companies hire the top 1%.
(Happy for someone to correct my numbers and the resulting percentage - it's based on a few Google searches).
Unless my numbers are way off, it's safe to say that over 99% of engineers in the world are not working at a FAANG. I stand by my claim that we should not be using what happens at FAANGs as reliable anecdotal evidence of the interview experience for most candidates.