Recently heard someone float another idea of this sorts ... the progressives might eventually turn on the trans, just like they did to other groups they've used in the past ... here's a progressive argument against transitioning:

"Why would you want to transition to a women? There is no gender, and by wanting to transition, you are acknowledging biology, which isn't real, therefore, something is wrong with you"

(Which of course they'd throw in some insults like "biggot" to such a statement)