Ruthanna Emrys’s “The Litany of Earth” uses the Cthulhu mythos to talk about a subject dear to Lovecraft’s heart—racial hatred. It uses a mythology created by a racist in the 1920s to tell a story that directly addresses racism, in a context of Elder races and people who worship Cthulhu and have been persecuted for it. It’s the kind of story that uses the familiar and the strange together to make you think and make you care. It’s an excellent story. It’s also a milestone.
Most of us take longer. Talent alone isn’t enough for most people, and craft skills take a little time to develop. It’s hard to say for sure what age most writers emerge, but if you look at the age of Campbell nominees for instance you see a median age of 33. (There’s a lot of variation of course. I was 37! And one of this year’s nominees, the wonderful Sofia Samatar, whose first novel A Stranger in Olondria is nominated for the Nebula, is 43.) But in general, you tend to see clusters of people coming into the field in their thirties with something to say and the skills to say it.