You said it's your last post, but I'm going to point its flaws out anyways.
In a lot of these cases, it feels like people use confirmation bias. You can tell that he's transgender, because you KNOW he's transgender. If I didn't know he was transgender, would I think he is? Probably not. If you didn't know, would really think he was just based off something as small as the eyes? Scar tissue is a thing too, because maybe he used to be overweight or had gynecomastia and had it removed. But you are using your own bias to say,"I would know that person is transgender" because you know that person is transgender. Your argument is flawed because the same argument can be applied to cis men. Similarly, a lot of people don't know someone is gay. But upon hearing that person is gay, they start instinctly looking for signs that person is gay. Then they confirm it to themselves that person is a homosexual. Your argument is flawed because you have reduced that person to small things, the twinkle of the eye, the curve of their smile, to deduce that hey, of course that person is trans, without realizing it.
Not that you don't have a point for some trans people, but for the guy you posted there? Grasping, very, very hard.