It’s easy to forget that the Netflix original film department is still rather young. Now some five years after launching, the streaming service is leaning into starry sequels in a big way, with detective stories like “Enola Holmes 2” and “Glass Onion: A Knives Out Story” this year. Next year brings more sequels with action pics “Extraction 2,” “The Old Guard 2,” comedies like “Murder Mystery 2” and more. Netflix executive Kira Goldberg says the company’s goal was always to create “stories and films and characters that we can return to.”