How do you figure that? I could see saying PJ, since there were a couple members in MLB, but Nirvana?
The only bands it'll hurt is Nirvana and Pear Jam. Alice In Chains, was allready sucessful before Nirvana was allready big touring with Metal acts like Megadeth and Slayer, and Soundgarden was a popular band in Seattle before Nirvana broke out.
MLB was going to have a major impact before Wood dying, and you could tell especially the supergroup Temple of the Dog was released their one album and somewhat big hit, Hunger Strike.