Simon & Garfunkel (1970)

Simon & Garfunkel's 1970 breakup remains the most bitter in folk-rock history, driven by Paul Simon's jealousy over Art Garfunkel's acting career and Garfunkel's resentment of Simon's creative control. Despite producing the era's best-selling album, Bridge Over Troubled Water, with 6x Platinum US sales, their live chemistry evaporated. While Fleetwood Mac's drama produced another three decades of music, Simon & Garfunkel's tension halted collaborations, proving that ego clashes can outweigh even platinum success.