Sci-fi book readership before and after Star Wars would be an interesting factoid to know. I think after Star Wars more folks started to first think of movies/TV when they hear the term ‘sci-fi.’ For me it will always be ‘books.’ But when I hear the term ‘western’ I first think of movies/TV.
FReegards
If you go to a comic book convention today, you will find that the focus is on actors and actresses from Game of Thrones and Marvel Comics movies and tv shows. Very few of the fans read. The artists are considered an afterthought and authors are "boring". The fans have more fun dressing up in self-made or purchased costumes.
They far outnumber the attendees who are there to look at or discuss books (with or without illustrations).