Most here maybe to young, but fact is Al and Tipper Gore started this parental advisory because of rock music. Not because of rap. Back in the 80s there was this huge thing about censorship and bands like Twisted Sister showed up in court to testify against bands being band. Obviously the bands won so instead they came out with this sticker instead. This is the short version. Just look up history or look up on videos on YouTube and you will see what I am talking about.
I do not believe it is fair to call Al Gore a racist for making the Parental Advisory label due to rap. I am not sure if that was it's original origin, but even if it was, it is a well earned label. There is music available to the public that has some hostile and inappropriate lyrics for children, I don't think anyone has been harmed by labels.
It is not even just for rap, its for rock and every other music genre, it just so happens that rappers swear a lot because they think it makes them look cool, and not all rappers are black so how is he even being racist? He is just giving an advisory