system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: It is not transphobic to not be attracted to transgender people and saying that it is hurts the cause.
gpt
You meet the most attractive person you've ever imagined, fall in love, have sex, then they tell you they were originally the opposite sex you're attracted to. On every physical level, emotional level, you were attracted to them and you saw no problem in any way, but now you've changed your mind purely on the basis of an idea.

Or better yet, it's the future. Throw in the fact that the genitals can be perfectly altered, hormones and hormonal changes can be perfectly adapted so that the sex a person was born with can be 100% transitioned to how they would be if they had the opposite physical development. They're incredibly attractive physically, emotionally, you get along perfectly, would you still say this person is unattractive because they aren't how they were originally?

Attraction can't be changed. You're attracted to all the subtleties around your preferred sex, no doubt. That's okay. On the same note, it would be like someone not liking overweight people, or really hairy people, or people they consider ugly. You could tack on "phobia" to any of those, logically, but if they could perfectly change themselves and their body to something you're attracted to and you still find yourself unattracted *because* of what they used to be, now it's pushing into direct discrimination, if not just purely ruined attraction like a bad taste in your mouth or something. 

So if you were unattracted to overweight people, but they lost weight before they met you, then you found them completely attractive, should you still be offended that they're not according to your attraction?

Remember, we're talking about humans here. HUMANS. That's the default condition. We can all develop to male or female, and that's why our genitals are made of all the same tissues in different order and structure.