Late nineties is pretty crap next to late sixties, or even mid-eighties.
1967 had The Doors, Sgt Pepper, The Grateful Dead, Surrealistic Pillow, The Velvet Underground & Nico, Smiley Smile, Are You Experienced?, Absolutely Free, Magical Mystery Tour, Buffalo Springfield Again, Disreali Gears, Strange Days, John Wesley Harding, The Piper at the Gates of Dawn & goodness knows what I've forgotten. And that's one year.
1968 has one of the best liver albums ever in Live At Folsom Prison, Astral Weeks, The Beatles, Beggars Banquet, Axis: Bold As Love, Electric Ladyland, The Hurdy Gurdy Man, In-A-Gadda-Da-Vida, The Kinks Are the Village Green Preservation Society, Wheels of Fire & White Light/White Heat.
1969 gave us Abbey Road, At San Quentin, Crosby, Stills & Nash, Grand Funk, Hot Rats, In The Court Of The Crimson King, Kick Out The Jams, Led Zeppelin I & II, Let It Bleed, Monster Movie, Phallus Dei, The Stooges, plus debuts from bands like Yes, The Allman Brothers, Genesis, Janis Joplin, & The Wailers.
As far as a 3 year period goes, I'd wager that takes a dump on any 3 consecutive years of the 90s.