Built to Spill, Pavement, Guided By Voices, Sebadoh, Radiohead, Elliott Smith,
Blonde Redhead, Neutral Milk Hotel, The Olivia Tremor Control, Grandaddy, Beck, Belle & Sebastian, Björk, Blur, Broadcast, Calexico, The Black Heart Procession, Thingy, Three Mile Pilot, Heavy Vegetable, Pinback, The Halo Benders, Causey Way, Clinic, Elf Power, Low, Ladytron, Mercury Rev, Rocket From the Crypt, etc. all formed and released great music in the 1990s. Not to mention great music by groups that formed in the 80s who released great music in the 1990s like The Flaming Lips, Fugazi, Dinosaur Jr., The Legendary Pink Dots, etc.
Some of my all-time favorite music is from that decade.