See, this is the common Nirvana/Cobain narrative, but much like the Jameis Winston narrative, it is very inaccurate and completely media driven. Nirvana's music wasn't angry. It was very positive, fun and funny. Most Nirvana songs were written while Cobain wasn't on heroin. He was living a nice artistic life while his girlfriend supported him by working at Boeing while he slept late, painted, wrote songs and rehearsed with the band. He was part of a thriving and vibrant artistic community in Olympia, Washington.
Then he got famous, got addicted and killed himself. All that had next to zero impact on the music since Cobain only wrote and handful of songs after he became a junkie and famous. Cobain was no different than a lot of people that had it rough growing up. He was very creative, talented and good looking. It's good media and marketing to sell the tortured artist, but it's not true.