You really think so? Then take a look at these so-called similar artists found on each of the following artists among the first 50 artists listed:
Metallica - System of a Down, Slipknot, Godsmack, KoRn, Disturbed, Rammstein, The Offspring, Pink Floyd, Led Zeppelin, Children of Bodom, In Flames, Apocalyptica, Alice in Chains, Bullet For My Valentine, Lamb of God, Stone Sour, Nirvana, Limp Bizkit, Rage Against the Machine, Deep Purple, Nightwish
--You really think nu metal like KoRn and Slipknot sound the same? When was Pink Floyd known for making headbashing tunes? I never knew Offspring was a metal band. I didn't know Metallica had harsh vocals like Children of Bodom, Lamb of God, and In Flames! I didn't know Metallica had rap vocals like Limp Bizkit and Rage Against the Machine. And I most certainly think Led Zeppelin is a true metal band since thrash and heavy metal is the first thing that comes to mind when someone says Led Zeppelin
The Offspring - Papa Roach, Limp Bizkit, Metallica, System of a Down, Red Hot Chili Peppers, Foo Fighters, Nickelback, Godsmack, Three Days Grace, Rage Against the Machine, AC/DC, KoRn, Bullet For My Valentine, 3 Doors Down, Disturbed, Hollywood Undead, Slipknot, Guano Apes, P.O.D., In Flames, Serj Tankian, Dope, Breaking Benjamin, Static-X, NIrvana, DragonForce, Puddle of Mudd, Iron Maiden, Linkin Park, Rammstein
--So wait, I'm supposed to believe that the nu metal craze of the 90s featured The Offspring? I'm supposed to believe Offspring played funk rock music like RHCP. I'm supposed to believe Offspring is a rap-oriented group like RATM, LP, and Hollywood Undead? A post-grunge outfit LIKE FUCKING NICKELBACK? In Flames did punk rock or pop punk? This is news to me!!!
Nirvana - Sex Pistols, Metallica, Led Zeppelin, The Doors, Guns N' Roses, The White Stripes, Ramones, System of a Down, Joy Division, Korn, The Beatles, Queens of the Stone Age, Pink Floyd, Green Day, Marilyn Manson
Gee, Nirvana is hard rock like Led Zeppelin. And they play psychedelic music like Pink Floyd and The Doors...obviously the Beatles and their happy pop and rock and roll is similar to Nirvana and their negative creep grunge sounds. And obviously it's nu metal since it's similar to KoRn and SOAD (I consider SOAD part of the nu metal scene but not as a nu metal band).
And there's more out there. This is all thanks to the brilliant formula for finding similar artists. Congratulations, if you love Guns N' Roses, you will love Nirvana (and vice versa).