It seems you have a soapbox you're unwilling to budge from, despite having nothing more than a couple of (sometimes scattered) anecdotes. However, here's something interesting that is based in fact.
It's likely hard to pinpoint the exact start of gangsta rap. Early rap with Run DMC and others started in the early 80s, but the first real example of rough stuff came with NWA. Their Straight Outta Compton album came out in 1988. That's probably as good a starting place as any to determine the birth of Gangsta Rap.
How about this? The crime rate has been falling precipitously since that time. The crime rate in 1988 for violent crime in America was 637 incidents per 100,000 residents in the USA. In 2019, it had dropped all the way to 379 per 100,000 residents. That's a MASSIVE drop. So, in the time where you feel that gangsta rap has been a menace to society (see what I did there?), the crime rate has been significantly lower.
Actually, those glory days of the 1970's where music was better and not about violence? You guessed it, the US had a higher violent crime rate then than it does now. Sorry if that doesn't fit the narrative, though. Murder rate from 1970-1979 ranged from 7.9 to 9.8 murders per 100,000 people. From 2010-2019? From 4.4 to 5.4 murders per 100,000...almost cut in half.
https://www.disastercenter.com/crime/uscrime.htm https://www.statista.com/statistics/191219/reported-viole... /