COMPLETELY DIFFERENT CULTURE.
Rock is different because there are a lot of different types of white “cultures” and the music reflected the ever changing tastes of what white kids consider cool.
The black experience is a bit more uniform. Most black people have a DIRECT connection to street money culture. Even if they are not in it, they are tied to it by family who still live in the “hood”.
Once street money culture took over the rap game, there was no going back. Unfortunately, the richest people most (not all) black people know personally got their wealth from street money. Until that changes, there won’t be much change to the most popular forms of rap that emphasize lavish lifestyles and street money culture.
If America ended the narcotics prohibition and made easy money harder to get, you may see a change in this trend.
Hip hop has been about flaunting money, girls, and machismo for almost 30 years now. It has been about that way MUCH longer than positive Afrocentrism, house parties, and rocking the mic.
It won’t change until America owns up to its sins and admit to what they REALLY did to us. It won’t happen though. The state of the black community at large didn’t just materlize itself magically out of thin air. It took a tremendous effort and vast resources both intellectual and material to create and maintain the current state.
The violent, boastful, hyper sexual black thug was designed, modeled, and manufactured by America just like the automobile or light bulbs with premeditated intent with a known end game.
There is no will to change this in any real, effective way that addresses the real issues that caused and perpetuate the current situation. So you are probably resigned to listening to old records for a sense of nostalgia.
Word of advice though. There is solid hip hop out there that reminds you of the old days. You won’t hear it on the radio though. You gotta dig to find those diamonds.