TLC performs at Concord Pavilion in Concord, Calif. on July 9, 2023. Sean Liming/STAFF. CONCORD, Calif. — Gen-Xers never forgot when TLC and En Vogue—years before a child was a twinkle in Destiny’s eye—ruled R&B and MTV. Dancehall artist Shaggy came along soon after as the nerdy, sex-starved Mr.…