Didn't even remember that, that's how much I cared about the sequels.
Hollywood is far from out of ideas. It's the economics of the industry at play. The original ideas that hollywood produces get made into series. Big budget movies are very risky and it's a much safer bet to go with a familiar concept, like comic characters, reboots, remakes, best-selling books, etc. If you have a really good idea for a drama, they're making it into a series now.