Rock music died from the mainstream for two main reasons:
1. After MTV and other music channels stopped playing music, it stopped introducing casual audiences to bands and it stopped giving newer bands a bigger spotlight. Rock music became more and more niche between the mid-2000s and 2010s. The sub-genres also became super segmented.
2. The Telecommunications Act of 1996 basically killed independent radio and TV stations. It all became oligopolized by a small handful of corporations. With that local and underground bands couldn't get played and the playlists became very standardized on rock stations, while on Top 40 stations they just gradually stopped playing rock music outright. Underground rappers from different regions suffered too, including New York. At least radio stations in the South and California play their local rappers.
I don't know how it was or is in other states, but NYC didn't even have a hard rock station, at least in the 2000s and 2010s, and NYC is the largest media market. The closest thing was Seton Hall college radio from New Jersey which often played metal but the reception on that was trash.
