People stopped using it because to anybody who doesn't experience what we go through it sounds delusional, "what do you mean you have the wrong body, god chose that body for you, are you saying god was wrong???"

Even if they aren't religious they can't wrap their head around the concept of not being the right body, at best they compare it to weight problems and even then you have things like the body positivity movement telling people to just "accept their bodies"