See the sentence immediately following the one you quoted. Interviewing is famously prone to subconscious bias, and having someone who is familiar with the proc

See the sentence immediately following the one you quoted. Interviewing is famously prone to subconscious bias, and having someone who is familiar with the process can give people a big leg up: they’re going into it confident that they belong there and familiar with the structure and general types of questions (this is the same reason why rich people pay for test prep classes for their kids even though those won’t fundamentally change their kid’s intelligence) and cultural literacy builds rapport with the interviewers - if they think of you as an in-group member, they’ll rate you more favorably and be more understanding about mistakes. Again, absolutely none of that is cheating - humans are just prone to thinking we’re far more rational than we actually are and there’s something like half a century of psychology and neuroscience studies showing that it’s both significant and requires effort to correct for.