I think music in general has lost it's meaning. Nobody listens to anything that means anything. Rap, Rock, Pop, everything. Today's society is just so stupid sometimes. If nobody noticed I can just name a few examples of modern stupidity.
4chan, all southern rappers, Soulja boy, emos, ignorant atheists, civil rights leaders who want to keep power to racial slurs, theists who don't know anything about their religion and use it merely as a brand, ridiculous censorship, people who think macs are "better" than PCs, youtube replacing conventional T.V, destruction of the English language by modern celebrities, people who wear the naruto head band things as casual attire, people who believe the earth is flat, people who pick sides in the political spectrum just for the label, and anonymous.
All that is mainstream is usually pretty stupid sometimes. Because of this stupidity, most people never hear about any good rappers. Stupid people usually play on the radio because "CRANK DAT SOULJA BOY" is much more catchier than good rappers like Nas, Rakim, and KRS-One just to name a few. Same thing with rock I think. Rock from the 70's to 90's were good, but this generation's rock just doesn't have any talent in it anymore.