Yeah, yeah, Cassandra Clare got her start writing fanfic, old news.
Rebecca Thorne wrote She-Ra fanfic before writing Tomes & Tea.
Matt Dinniman wrote GI Joe and Transformers crossover fanfic before writing Dungeon Crawler Carl.
Pierce Brown wrote Greek Mythology fanfic before writing Red Rising.
Andy Weir wrote Ready Player One fanfic that later got canonized by Ernest Cline before writing The Martian.
Fanfic has never been, and will never be inferior to published works, and writing one does not discredit or devalue the quality of your work when writing another.
