Well, if your “mom” looks as cartoonishly masculine as some of these lesbians — the ones where you really can’t tell for sure that she is not a he — a boy might look at that woman and, seeing only a gross caricature of “manliness,” yet being told that very masculine person is a woman, and he might conclude, “they said I’m a boy, but I must be a girl because I’m like my ‘mom’ who, um, looks very much like a man.”
So imagine the surprise of the boy who, upon concluding that he must be a girl because he looks and acts like the extremely masculine and cartoonishly “manly” woman raising him, then promptly gets put into ribbows and pink tutus and praised for wearing nail polish and girly glasses.
What happens if, years from now, he can't afford all these things (or the economy goes bust)? What does he become then? He'll be a hairy, half man, half woman.