Just because someone cuts their dick off doesn't make them female (or any other fairy tale gender). It makes them a dickless male.
Scientifically speaking there are only 2 sexes. Male and Female. Regardless of what appendages are added or subtracted, biologically (ie. scientifically) one is still the male or female they started as.
So, the real issue is: Why must people be required to live in the make believe world of someone else?
If someone wants to dress like a woman, alter their body to be more woman like, go enjoy yourself. Why must I be forced, contrary to science, to accept that this type of person is a woman? Why must society in legal terms accept this type of person as a legal woman? Women's rights have been hijacked by imposters.