In one of Norman Mailer's last interviews he stated the era of the serious writer is over, everything is television and Hollywood. My movie loving friends agree with this, but I'm giving you the same challenge I give them.
I bet you can name ten novelist, ten playwrites, and ten poets from the top of your head without thinking. Now name ten screenwriters from the top of your head without thinking if you can.
Danshiell Hammet/ Raymond Chandler never considered themselves screenwriters. They went to Hollywood because of the lack of money they were making during the Depression. Hammet would have never work in So Cal had it not been for the success of Maltese and Chandler never cared if anyone understood his screenplays. During the filming of the Big Sleep a producer called and said there was a hole in the plot, he had never resolved the murder of one of the characters. Chandler told him to read the book cause he couldn't remember.
We all know Faulkner as a novelist, but would you count him as a screen writer? maybe, but a novelist was how we identify him. And didn't Phillip Epstein and Sidney Howard make a name for themselves for stage writing first? I don't mean to tear a part your list. you are correct in naming ten. I just can't think of ten that are legitamately screenwriters first. I think Hollywood has poached the greats, early on was lucky to give carriers to good ones, but with the exception of a very few it is still (writing wise) not as populated by greats as the other mediums.
Of course there is always Woody Allen. He was a writer first, TV and a few publications, but he ultimately is a film writer/director.
Here's my 10
Quinton Terantino Woody Allen Norman Lear Joss Whedon Spike Lee Larry David Charlie Kaufman George Lucas Barry Levinson Norman Lear Scott Kaufer
Nope. Can't even name one. Actually, I'd have difficulty naming ten poets as well.(embarassed red face). I might be able to quote of the lines that have most impact on me in a book though...doesn't count, does it?