A world in which gender transition were a trivial weekend occurrence would not excuse the gender wage gap. If conversion therapy were effective, it would still not be moral to imprison people for being gay. Being able to lighten one's skin does not, and should not, excuse the shooting of Black people at traffic stops.
For some of this, this isn't an armchair "design space". Some of us still have people shouting "faggot" at us from passing cars. Some of us have strangers threatening to kill us in the supermarket. Some of us have been fired when our old names were found out. Some of us are trying to figure out how to tell our children how not to be murdered. These kinds of discrimination are not "perfectly legitimate" social choices. They have impact on actual human beings.