Wendy Carlos is very famous, just very low key. Money (huge piles of it, I'm sure in her case a mountain piled up the to sun) can buy you a lot of privacy. You can be so rich that you can live on the down low, even when everyone knows. She is just not famous for being trans, having done something else in her life to be really, really, famous (at least within the community of people who share her passion, music) for.