I think for many trans people, including myself, dysphoria has a way of sneaking up on you in a way that you really doubt yourself like T.K.G.W. said. He put it perfectly. I was not aware of my dysphoria or rather the feeling of it until puberty, which was around age 13. It really was exacerbated when I would begin comparing the way my body developed with my brother and other biological males. Since I was a child, I once thought that everyone began their lives with a vulva and as they matured would grow a phallus.
When I used to bathe with my bro as toddlers, around age 4 or 5, I used to ask myself even back then, "When will I get one of those down there?" 'Those,' being a penis. But it never occurred to me until a year ago that all this time, I was very unsatisfied with having a female body and is probably a huge contributor to my other mental issues. I think that last part can be said for many transmen, but in the case of a transwoman it would obviously be the unsatisfactory feeling of having a male body. When so many people claim us to be something we aren't, how can we find the rightful judgement and strength within ourselves to ever say otherwise? So yes, realizing that we are dysphoric, in the case of trans people who experience it, would make sense to make us happy because it helps us to identify an underlying problem that can lead to treatment. No wonder that would make us happy. 🙂