It's a weird thing to realize but fundamentally, Hollywood doesn't know how to make movies. No really. Consider the ratio of flop movies to classics. Now look at cars and compare the ratio of flops to cars people want to drive. Somehow other companies manage it but Hollywood has a terrible batting average.
You see tons of imitative crap and the idea that "X" will make money and "Y" movies don't when in reality, good movies make money and bad movies don't. The problem is that "Good" is hard and Hollywood doesn't grok it very well. Also there's a natural human tendency to try to go with a "great man" narrative and make it all about the person in charge, forgetting the fifteen dozen other people who actually made it work, and Hollywood runs on name recognition which makes the fifteen dozen people harder to find and realize they contributed.
Star Wars is probably the most useful example. For decades it was "The Genius of George Lucas" and it was only until he turned out an array of turds and poorly-received remakes and sequels that the truth of Star Wars came to light; it was George Lucas' skill at special effects... and his wife being surprisingly good at rewriting and doctoring the script... and the luck of managing to get an incredible array of great actors first try... and Irvin Kirshner turning out to be an excellent director who was willing to tell George "that's stupid."
But you can't just happen to have all those good things happen at once over and over without a lot of work and avoiding "great man" name recognition that Hollywood runs off of, so Hollywood can't duplicate Star Wars.