Can't to fates while leveling - due to other players

[Dewslam]

You could fly there too though? You aren't slower in the air. Unlocking flight is unrelated to ranking up your Shared FATE for the area.
Also you can join a party, people host Shared FATE farm parties in party finder all the time. It's a bit easier when you're with a group.

You can't unlock flight for two of the zones until much later in the story.