Two dialects exist that have trouble understanding each other. You declare one of them to be "broken" and "inferior." Why that one and not the other one? Surely we could say that AAVE is totally fine and it's "Standard English" that's broken? When you pick the one spoken by black people as the "broken" one, it's hard to see any motivation other than racism.
Well, for one, one is a more established language, with a longer history (literals and otherwise), written rules, plethora of books, and billions of speakers the world over.
In fact, it was the AAVE that's derived from English and not the other way around. Without English there would be no AAVE.
Plus it's also tied to a particular subgroup (and not even for all of its communicational needs).
Oh, and about all that racism stuff that easily flows, I don't have a horse in this race (no pun intended) as I'm not American, and we didn't really do slavery. If anything, when my people came to the US they were treated exactly like blacks were treated at the time by the racist white majority, KKK-visits included.
This is logic that suggests we that all our comments should read like Beowulf, or at least Chaucer; after all, the dialect we speak is derived from older ones far further from our comprehension than AAVE.
I have to hand it to you on Beowulf example. I remember learning about that in our literature class along with descriptions of Old, Middle and New English. Or something like that. What jumped out at me was how Old English looked German or something quite different from "English" as I was taught. Everyone in the class abhorred it as "not English." Turns out, our ancestors could've made the same gripes about our "dialect of English" that people are making about AAVE. Tripped me out.
There are many varieties of English. I'm not aware of any single dialect that has anything close to a billion speakers. Dividing the complex universe of English dialects into AAVE and not-AAVE just emphasizes the unfair treatment this one particular dialect gets.
