Please. Calling people "ghetto trash" is in bad taste. Calling a kid "ghetto trash" on a forum and defending that sort of statement just means that some of us have become what we despise.
And while a person may not have had racial intentions in using the term "ghetto trash" (to say nothing of fabricated "ebonics" dialogue), you would have to be an idiot to not know that someone would take it as such.
As for substantiation, I posted the link to the reproduction of the thread (with a note that it might have been changed). If you don't count that as substantiation, then you and I have different definitions of substantiation.
I, too, am curious about your motivations. I am generally for truth. I find that side usually wins in the end. You are free to be motivated by whatever you like.