"Femme" is a word specific to the lesbian community, and he didn't use it by accident. Many female-attracted MtFs these days get off on calling themselves "lesbians" (lol), pretending that actual lesbians are capable of being attracted to males like them, and co-opting lesbian terminology & spaces (e.g. "femme"; r/femmelesbians...)

Lesbians are more "validating" and can better produce "gender euphoria" for MtFs than bi women can, because lesbians are ONLY attracted to women. In other words, many MtFs have gotten into the nasty habit of expecting lesbians to offer up our own bodies as some sort of dehumanizing litmus test to "validate" their sense of womanhood with our lesbian companionship.