I was watching a show on Netflix about Hollywood movie cliches when I learned about this.
Apparently, the scream was from the 1951 film Distant Drums, where an actor screams as he is attacked by an alligator. It ended up being used in other films and now is the standard for screams (rising to the point of an inside joke in Hollywood) used in many movies including blockbusters
https://www.kennedy-center.org/education/resources-for-educators/classroom-resources/media-and-interactives/media/media-arts/sound-design-and-the-wilhelm-scream/
https://en.wikipedia.org/wiki/Wilhelm_scream