It's an excellent question.
With many excellent answers on here already.
Some further thoughts.
Academia is really precarious these days, jobs are hard to come by/hold on to, I see why academics are unwilling to risk speaking out on this, when their jobs are threatened already. Why make a bad situation worse?
There were some great posts on here about a week ago about the rise of post modern theory and the impact that's had on magical thinking, breaking down boundaries, everything's possible mentality.
Academics tend towards the left and I feel the left focus on how humans could/should be in an ideal world, whereas the right is more grounded in how they actually are in reality. That's obviously a huge generalisation, but simplifying for this discussion.
I see how the left gravitates towards the positive potential here (people breaking free from the constraints of their bodies to be their true selves, the triumph of an oppressed class of people) without engaging with the more problematic realities (sex changes not actually being possible or 'the answer' for many, the capacity for trans rights to be exploited for money, power, sexual kicks).
Plus the point about white, middle class guilt is a great one.
So I am starting to see why, though the denial or basic scientific principles from academics will always blow my mind.