No one should "love" the kind of rap music that the author is talking about. The love and worship of "gangsta rap" has the black community in shambles.
Do you seriously think "gangsta rap" is the cause of ills among blacks? Do you similarly blame violent video games for teen/young adult violence?
Admittedly, gangsta rap that describes the ways of inner-city life is an artistic statement. I suspect the parent was talking about the certain sub-genre of gangsta rap that eulogizes and encourages a violent life.
To answer your first question (even thought you asked the parent), I can't believe that music of any form can possibly be the cause of ills among the black community.
That's because you aren't black, and you wouldn't know. It's not just music, it's the mainstream media as a whole, and how they depict a successful black.
The black youth don't get to see the successful black businessman, lawyer, doctor or politician. The ghetto drug dealer who became a rapper and now has millions, athlete, etc. are the only success stories we are fed with, on a daily basis.
Same thing with metal, in a way... a lot of the metal I listen to glorifies violence, satanism, drug use, and all manners of excess related to sex, alcohol, etc. But while I like sex, alcohol and rock & roll as much as anybody, just listening to metal doesn't mean I'm going to start worshiping satan and go burn down a church.
That said, I don't disagree with your overall point, to the extent that I can understand it as a white person. It reminds me of what Richard Pryor said about how black youths screw themselves by refusing to speak proper English, study hard in school, etc. Unfortunately when a black man says something like that, he gets labeled "Uncle Tom" and what-not. :-(