So you think white supremacists are targeting Bill Cosby because he told black people to pull their pants up and get educated?

No offense, but you are displaying a stunning level of ignorance of race relations and the political atmosphere of this country.
Let me try to explain some things to you. Bill Cosby is the #1 black tool of white supremacist narratives in this country. If you were even passingly familiar with the national political discourse as it relates to black people you would know this. When Cosby came out with his little "pull your pants up Jerome" routines 9 years ago, he was instantly embraced by the right wing (i.e. white supremacists) and this is not disputable. Every racist talk radio show host, politician, wannabe pundit and average cac on youtube or yahoo hailed him a hero.
In attempting to define and establish causation for the gaps in achievement and socioeconomic status between blacks and whites in the country, there are generally two basic lines of thinking. One is that there are structural inequalities as they pertain to race that are the primary causative factors. The other is that structural racism is over or not very relevant today, and black people are in the position we're in because we have a depraved culture, and the problems could be remedied if we just took personal responsibility and stopped blaming white people.
And there's gray area in between of course, but Cosby is firmly entrenched and committed to the latter narrative, which is the same narrative that white supremacists embrace. That's why he is a hero to white supremacists. I guess you just don't follow political landscape at all or you would know this. "Bill Cosby is right" became as commonplace as random shots at Al Sharpton and Jesse Jackson among the right wing (white supremacist) community.
There was a GOP primary debate where a black guy who was with his son asked the nominees what can be done about violence in his community, and Mitt Romney responded by saying "God bless Bill Cosby for telling the truth" to an applauding audience. That's because Mitt Romney is a shrewd politician, and he knew that would play to a racist ass GOP primary debate crowd.
Sean Hannity's been on his dikk for years.
Rush Limbaugh defending him.
http://radio.foxnews.com/2014/11/18/limbaugh-defends-cosby-blames-cnn/
Glenn Beck defending him.
http://www.mediaite.com/online/glenn-beck-ap-raped-bill-cosby/
Jesse Lee Peterson, who is a klansman in blackface defending him.
http://www.wnd.com/2014/11/attack-on-bill-cosby-is-no-laughing-matter/
Bill Cosby is a tool of white supremacy. In his defense, I don't think that's what he wanted, but it is what he became. And he is a tool of white supremacy because he makes white supremacist arguments. "Pull your pants up and go to school" is not some profound insight that Bill Cosby discovered and no one ever said before. It's advice a father or older sibling might give to their son. It's not a socioeconomic explanation of macro-world phenomena. Black people are not struggling because they don't pull their pants up. Black people are struggling because they have never had the same access to education, healthcare, nutrition, safety, and employment and even when we overcome obstacles, we still face racism. The "pull your pants up" narrative is the same reasoning white supremacists use: "racism doesn't exist, black people are lazy criminals on welfare who need to stop whining and get a job." Bill Cosby having the cache and credibility he had among black people and the general public made him the perfect mouthpiece for these white supremacist narratives.
That is what he said.
"People getting shot in the back of the head for stealing a piece of pound cake. And they're we're all outraged, the cops shouldn't have shot him. What the hell was he doing with the pound cake in his hands?"

That sounds like something a KKK member would've said. His series of "black people ain't shyt" speeches weren't just supporting of white supremacist narratives, but were extremely venomous and mean-spirited. He also said black people are naming their kids "Taliqua and Muhammad and all that crap and they're all in jail" and said some shyt about how black people need DNA cards to know they're not having sex with their grandmother.