Lucas is the one who claims it was always called that but it confused the executives at Fox and Alan Ladd Jr.
The first time the title surfaced was in the public script not the shooting script edited by Carol Titleman in the art of Star Wars. Unless i am mistaken and my memory is failing me again. That was well before 1981 that was in the 1970s. Not sure when it was first published. I don’t have a first edition at hand.
Funny thing even when the Episode IV title was old news and it had A New Hope at the beginning the film was still just called Star Wars. I don’t remember a single person calling it a new hope. I even have VHS copies and Laserdiscs where it just says Star Wars. The standee displays and advertising was for Star Wars.