Actually, Lewis never specified what his biological sex was. Here is the an important clue (added emphasis):
Salient details: I have lived as trans for 15 years, and I identify as transgender and transsexual and androgynous and PASS sometimes as a (YOUNG) BOY but usually I am read as female, especially when I open my mouth. I have never taken hormones and have a high voice and a wide smile and pretty eyes. (Yeah, I’m pretty hot for a radio personality.) (Also, people are trifling and don’t think men can have wide smiles and pretty eyes.) Another important detail is that I don’t really give a shit if people see me as “male” because I don’t identify as male, but I also don’t identify as female.
The key words are identify, pass, and read.
From this we can extrapolate that Lewis is most likely not biologically male. But that is Lewis’ business anyway.