"Most of them written in the pre-enlightenment era, which is where we seem to be headed."
I think a lot of this stuff has to do with the decrease in religious belief and patriotism. I think many people need a belief system to get them through, to fight for, to give their life meaning. For some reason, logic/science just doesn't do it for such people. Maybe it's the feeling of community or the need to believe in something higher than themselves. In the old days, this need was fulfilled by the church or by the feeling that we were fighting to make a better country or that our country was better than other people's. These days, it's the belief that we're better than those horrible terfs and the social need is fulfilled by twitter and tumblr.
This, combined with the rampant individualism/look at me culture, and the extreme gender stereotypes we say these days (especially for women: manicure parties for six year olds/contouring everything/waist trainers/instagram influencers/Kardashians) has led to this.
I'm not that old, but if I'd told my mum that I wanted to be a boy, she'd have said 'that's nice dear' and told me to go and play. Now, it's psychiatrists and doctors and writing a blog about your toddler who is trans.