I see this "gotcha" repeated a lot and it's probably the stupidest one that I've ever heard. It really only works until the clothes come off.

If I happened to see a trans man that was somehow both my type and also could not be clocked as a woman (I know that I'm talking about unicorn, but let's roll with it), I'd probably experience some attraction. As soon as I find out that attractive man has a vagina, all of my attraction would be lost.

For an example that has nothing to do with being trans, let's say I see an actual man that is my type and I am attracted to him because of his looks. Before we get into bed, I talk to him for a bit and find out that he's super into decapitating kittens the moment they come out of the mother cat. He could be the hottest guy in the world, but I doubt I would find him any sort of attractive knowing that he enjoys something like that.

It's like these people don't understand that attraction based on outward physical characteristics is just one piece of a much larger puzzle that forms overall attraction to someone, and that when new puzzle pieces are added to make a more complete picture, sometimes that more complete picture is unattractive. Like if you were building a puzzle and the image looked like a bowl of chocolate ice cream, but when you finish building the puzzle, it's clearly a bowl of shit.