No, that’s not stereotyping.
Seems to be the “You Americans are so racist! Pretending you can tell someone’s race by hearing them speak!” hill. Despite all evidence pointing otherwise.
The irony is that this phenomenon is the actual consequence of living in a racist society. It’s not that we are so racist that we are deluding ourselves into believing something untrue. It’s that our society is so racist that white and black people have different accents.
Don’t make me come down there!
Hah! No, but really …
The term linguists use for what’s being called “voice” in this thread is phonation. For example, falsetto is a phonation.
I listened to McWhorter’s podcast when it first came out a few months ago. He’s making big claims, but I doubt his methodology is robust enough to fully support his claims. What he’s identifying are shadings in vowels that come from a Southern accent.
So why don’t white Southerners speak with the same accent? I think the Southernisms used by Black speakers that McWhorter is talking about are more conservative features of Southern speech, and that the influence of racism and segregation introduced innovations in white Southerners’ accents to differentiate them from Black ones.
The Old South accent died out with the last Confederate veterans. Listen to Tim Rozon playing Doc Holliday in Wynonna Earp on SyFy. Rozon has studied the Old South accent, probably by listening to scratchy cylinder recordings of elderly 19th-century Southerners, to reconstruct how somebody born in Georgia in 1851 would have talked. The Old South accent we’ve heard in cartoons with the stereotypical “Ah do declayuh” was the upper class variety, on which Rozon seems to have based his character (middle-class aspiring to upper class would be my guess for Doc Holliday’s accent). I think the working-class white & Black Old South accents would have been essentially similar, though.
As I was mulling this over, I noticed the video posted by Mr Dibble with the Black-sounding white guy; his accent sounds like a living fossil of working-class Old South speech. I’m suggesting that the Black accent features described by McWhorter are surviving traces of this Old South working-class accent.
Sounds like you’ve found an interesting topic for discussion! Perhaps you’d like to break it off into its own thread, as people looking for info on the original OP about youtube videos might not find that its what they’re looking for?