A little bit late to the game. I did not listen to 90s music when it came out, but I listen to a lot of it now. I don’t have the in-depth knowledge of every band from that era, especially the harder stuff. With that said:
1. Pearl Jam. I don’t even think this one is a question. Not only were they influential, but then you add the longevity.
2. Nirvana. With two of their three albums in the 90s, I guess you have to put Nirvana at number two. Nevermind pretty much put the nail in the coffin of every hairband that was still hanging around.
3. STP. I put that number three because I like them. Go pound sand if you think Soundgarden was better. Me don't care.
4. Goo Goo Dolls. I’m going off the reservation with this one. In recognition that the early 90s were vastly different from the late 90s, we should all look back at how ubiquitous GGD was after a boy named goo and dizzy up the girl. By 1999 they were everywhere. MTV, movie soundtracks, guest appearances. Johnny Rzeznik was the voice of pop/rock music for several years there. Maybe they could’ve been considered a 2000 band, but with those two albums being in the 90s I’m going to give them the unconventional nod.