Gay and transgender people have been around forever.. nearly 2,000 years ago Juvenal was writing about the political issues of the day in Rome and about gay marriage and a bunch of other modern-day problems.... (sorry about the old English translation - I couldn't find a better version I could copy/paste)..
On gay marriage, he was criticising the move to make it open and accepted -
""I have a ceremony to attend," quoth one, "at dawn to-morrow, in the Quirinal valley." "What is the occasion?" "No need to ask: a friend is taking to himself a husband; quite a small affair." Yes, and if we only live long enough, we shall see these things done openly: people will wish to see them reported among the news of the day. "
About transgender people, criticising the fact that they were starting to come out and be who they felt they were -
"but just where will men draw the limit, they see a high born lawyer dress in transparent chiffon, to public amazement, and prosecute loose living women?"
Realise that they are satires, so they're extremely scathing.. but he also touched on abortion, incest, lesbians, gay men that were in straight marriages (even suggesting it's good for the wife since the man will buy her a lot of jewels to keep her quiet and she could basically do what she wanted)....
Bottom line - these issues have been around for centuries..