Jalima1108 I would not think that revealing a person to come from a privileged background would exclude them from a job for which they were qualified.
The point of this is to ensure that people who are not given all the advantages may be recognised and helped to achieve their potential. It would also be a sieve for shaking out any snobbery, whereby people with (shorthand term) "posh" backgrounds get preferential treatment.
Jenny Murray of Woman's Hour has said how she is grateful that her mother sent her to elocution while she was a teenager, even though at the time she rebelled against it. She comes from the North of England, and the elocution taught her what, at the time was called "received speech" or "Oxford English". In her generation, she openly said, she knew she would not be employed by the BBC had she spoken with her northern accent. The regional accents are not prejudicial to employment now, thank goodness. However, more subtle prejudices can be at play.