Id certainly be dysphoric, but thats because I've had a male body for 39 years. But this is a disingenuous argument and beside the point, they didn't just wake up in another body one day, its the one they've always had. If the world's greatest athlete woke up in my body one day, I'd expect they'd be awfully dysphoric about the sudden change in athleticism, what they've dedicated their whole life to would be taken from them. I on the other hand have had decades to comes to terms with the fact that I won't ever be a professional athlete and have based my self-worth and identity on other qualities. I would have to be insane to say, 'but in my brain I was always a professional athlete and I was born in the wrong body and we are all gonna play pretend or else'.

P.S. - The doctors incorrectly assigned me as a peasant at birth, I was meant to be a member of the royal family. You will call me Baron von Phooey III and curtsy in my presence or I will have HR send you to sensitivity training