I knowingly met one between 0 and 25 years of age, and he was miserable, being the default victim of every prank and worse at and outside of school.

And I'm ashamed to say that I shared very negative opinions of homosexuality and even worse ones about transgender people; essentially a mirror of my times and place.

After 25 I started meeting more open gay people and my first (known) trans-woman and realized, to my shock, "these are just people". I decided from then on to stop being a bigot. I don't think it was a huge coincidence that some feelings I'd been struggling with post-16 or so suddenly made so much more sense and had me realize I was more than incidentally bi.