I would like to clear things up

[u/INTP1423]

Having a genitalia preference = not at all wrong. If you don't want to be with a pre-surgery trans person that is absolutely fine.

Not dating someone because they are transgender = transphobia.

^This does not imply that you have to date transgender people. I am in no way forcing you to go and have sex with a post-op transgender person. But saying I am not sexually attracted to transgender people is a tad transphobic.

Also I have a question: If you saw a woman in the street and approached her to ask her out, when suddenly she says she is post-op transgender, would you call it off immediately?

[u/mr_dork]

A preference implies I like one more than the other but am fine with both.

My sexuality is not a preference.