Login not working here for some reason....
Your standard can't really judge anything to be correct.
True, but I'm not using my standard, I'm using the standard of the thousands of people I hear speak standard American English.
Ebonics is simply poor English, no matter how many educated people speak it. I engage in hillbilly talk from time to time, and I enjoy it. But I don't expect anyone to accept it as correct. It's not.
In the context of a group of people, all of whom speak "hillbilly talk," and all of whom understand its nuances, it is perfectly correct. Speaking it in a classroom, or a boardroom, other than for effect, would certainly be incorrect.
But I do accept that there is change over time - so long as the change is good. I am tired of hearing that gay used to mean happy. It still means that. If the slang usage has replaced the actual meaning, that is just due to ignorance, and I won't accept it.
There is change over time,
and it is neither good nor bad. It simply is. "Gay" is a good example. It used to mean happy, and in the right context it still can. But it has acquired an additional meaning of homosexual. That's not slang anymore, any more than "dumb" (which you just used) only means "unable to speak." It now also means stupid.