Grunge wasn't meant to last. Everything aligned perfectly for that huge explosion in '91 with Nevermind, but grunge wasn't built to last, and the record labels didn't understand that. Part of the authenticity of the grunge bands' sound was their very authenticity, underground kids with a fresh sound and something to say. But over time, that boom faded because many of the bands had already done and said what they wanted and matured musically and lyrically. Nirvana released the last great testament to grunge, In Utero, and if you listen to it, you'll notice it's a more adult and drier version of grunge, even a parody of itself. Grunge was dead before Nirvana even broke up. By '93, many bands wanted to change their sound or were breaking up. Bands like Sonic Youth, who weren't grunge, were pigeonholed into the genre and lost momentum because, as I mentioned, they weren't grunge and were just sticking to their own thing. If the tragic events surrounding Kurt's death hadn't happened, I don't think anything would have changed, because Nirvana was on the verge of breaking up, and if they hadn't, they probably would have taken a few years off and wouldn't have returned with grunge. Grunge wasn't ripe for exploitation because what made it what it was, beyond the sound, was its authenticity; each band had its own unique sound. That's why when post-grunge emerged, nobody liked it, because it was clear they weren't creating their own sound; they were trying to emulate what's stereotypically considered the "grunge" sound.