the article recognizes that nowadays there is a distinction between 'biological sex' which is based on physical evidence and 'gender'. the latter is based on personal preference of the individual at a certain point in time, not genetic predestined nor unchangeable.
the lbtg+ community is concerned by the spin-offs from the gender diversifying.
if you accept people who claim to be mentally healthy while denying their biological sex as their gender, then what to to with the following claims?
a trans ager: http://www.mrctv.org/blog/52-year-old-father-lives-6-year-old-girl
a trans species: http://www.thedailysheeple.com/transanimal-this-lady-really-believes-shes-a-cat-trapped-in-a-humans-body_022016
a trans mythical being: http://www.dailymail.co.uk/femail/article-3524063/Transgender-woman-Eva-Tiamat-Medusa-ears-nose-removed-dragon-lady.html
now, these web postings could be parodies, fake and ridiculing the transgender issue. but the problems remains, why accept trans gender but not the trans .... ?