I grew up in NYC and went to school in Boston. They each have their own way of talking (anyone whose listened to JFK’s speeches or Bugs Bunny knows this) but when someone becomes a journalist or actor they try to talk like Walter Cronkite. They adapt the mode of talking of the middle of the country because that is easiest for most people to understand.
As another example of how people try to change their speech patterns — take a look at the movie My Fair Lady. Everyone in there is white, so it’s not about race. It’s about class. The little flower girl can’t speak like an upper class lady so no matter how she’s dressed she will be treated like a flower girl. When she learns to talk like a lady, she is treated like one.
My parents came to this country from India. They worked on losing their accent because that made it easier to assimilate.
Historically in this country it wasn’t just immigrants or newly freed slaves who tried to emulate a different way of talking. White actors and actresses who wanted to make it in Hollywood took speech lessons too, at least after the motion pictures got sound.
And it’s part and parcel of a variety of other things. Like tattoos. Someone with a discrete tattoo on their lower back won’t have a problem in interviews but someone whose got them on the face or neck might. Same with so many other things.
Is it fair? It’s reality.
BTW, just to be clear — racism DOES exist. It IS evil. No argument with you on that!