Unlock with No Level 80 Characters?
The Story Journal
To go along with this change, we’re modifying the story Journal in your character’s Hero Panel so it will track all of your character’s story steps. From that panel, characters who are level 80 will be able to select between playing their personal story and the Living World story. For the Living World story, you’ll be able to select which unlocked episode you’d like to play. Characters under level 80 will be able to see the available episodes, but will not be able to play them until they reach level 80. Think of the Living World story as the constantly expanding continuation of your character’s storyline once they reach level 80.
https://www.guildwars2.com/en/news/introducing-the-story-journal/
Thanks for the quote.