MEMORABLE =/= ICONIC.
An icon is easily recognizable. An icon represents/symbolizes something; something being a group of people, a period of time, a genre of music/film, the culture of a group of people, etc.
Examples of iconic things and people:
Iconic for American culture:
Iconic for ALL music videos, the MTV era and all modern Popular culture:
Iconic for 1980s Pop:
Iconic for the Teen Bubblegum Pop movement of the late 90s/early 00s and all Teen Pop culture:
Iconic for 2000s Pop culture:
Iconic Black Female Performers

:
Iconic for the American Civil Rights Movement:
Iconic for Michael Jackson and his career:
Iconic for Marilyn Monroe, Hollywood and American female celebrities:
I could go on and on.