Some of those guys are more SGs. Tracy has the size to be a SF but if I'm not mistaken he's played at SG a lot. Joe Johnson is a SG.
I think this list more than anything highlights the fact that there aren't very many amazing SFs in the league - just a lot of solid ones.
Perhaps in the next decade you'll see more superstar SFs with Kevin Durant already blossoming, Granger taking the leap last year, Beasley with a lot of potential, and LeBron and Melo with a lot of their careers still ahead of them.