This is all totally off-topic, but there is one part of your argument that merits discussion. Pointing out that a few people have experienced very lucrative social mobility is not evidence of the system as a whole being conducive to it. In fact, such arguments serve the exact opposite goal by thwarting meaningful discussion of social and economic policy. A handy thought experiment from Cracked makes it more clear:
Let's say there are a hundred of you and your friends all locked in a room, and you're all starving. I walk in, and out of my fat wallet I pull a wad of bills that it more money than you'd make in a year. I set it on a table, and say, "the last one of you left alive gets this pile of money." Then, when all your friends are dead, you get rich, and I say, "see? The system is fair: any one of you can become a rich person, if only you try hard enough. It deliberately conflates "any of you can get rich" with "all of you will get rich." And you and your friends are so busy fighting each other that nobody is asking why there was only money for one of you in the first place.
Dr. Dre may have become a billionaire, but he grew up in a neighborhood systematically ghettoized, and the majority of the kids he grew up with ended up dead or in jail, and almost all of them stayed poor.