There were definitely a lot of building blocks.

You cannot deny that the tabula rasa/blank slate nonsense of the social constructionists didn’t have a massive role in developing gender identity theory and feminists were massively involved in pushing that stuff, because it removed all the pesky biological sex differences - meaning all inequalities were down to patriarchy - which complicated their arguments about women and men. But in heavily pushing that shit they opened the door for the devil of troonery and invited him into the stall with his ladypenis. Are they to blame for it all, absolutely not, but I still have feminist friends who adamantly refuse to admit there are biological differences between men and women (except for the baby making equipment).

There will no doubt be future PhD theses written on the causal elements of troonery, and someone will synthesise all the disparate social sciences and humanities pieces that lead us down this road. Hopefully they also compile a list of all the people who bear responsibility for the industrial abuse of children that it is bringing about.