Unfortunately, or maybe fortunately, there are certain actors who will always be known for that one role. Some embrace it while others wish they'd never played that character. Have no idea how Beatty felt about it, but there's no way anyone with any age on them, can see him and not think about him squealing like a pig in Deliverance. I had no idea that was his very first movie, but according to the wiki's, he was in 160 films after that.
He was in Shooter, a B movie with Mark Wahlberg that I love for some reason. Beatty played a U.S. Senator and gave one of my favorite lines. "There's always a confused soul who thinks one man can change the world, and you have to kill him to convince him otherwise."