Elvis
Michael Jackson
James Brown
Aretha
Bob Dylan
Elton John
Frank Sinatra
Prince
Bob Marley
Paul McCartney
Probably, at least, 50 more if I don't include groups. Joel's popularity has been maintained by the people who liked him in the 80's. Unlike the list I provided, there are not new generations of fans discovering him and, in fact, very few of his songs endure. I actually went to a Billy Joel concert in around 1978 and enjoyed it.