Starting at the end of World War Two adults stopped going to the movies. In 1946, 70 percent of the entire population who could walk attended the cinema weekly. Now it's less than 9%. And most of that 9% is 12-25 year olds. Teens like escapist shit. They always have. They used to call them B-movies. Now that teens are effectively the only important market, it's all B-movies.
Jaws, Star Wars, and the coming of the blockbuster era was just Hollywood finally realizing that there was no point in marketing films to "everyone" anymore. They've always been whores. Get over it.
"Popcorn pictures have always ruled. Why do people go see them? Why is the public so stupid? That's not my fault." -George Lucas