I can relate to the above, Oak. A few months ago, one of the Social Studies teachers from my middle school (the one I went to, not the one I taught at) died. He was not my teacher, but I knew him from student government. He was my former boyfriend's teacher and coach. I often thought this man disliked me and viewed him as typical jock guy. I also thought he was old when I knew him.
Turns out, he had worked for very many important social justice causes for his whole life. And he was the same age as my dad, which means he was in his forties when I knew him. I messaged my former boyfriend, as he lives in another state, and he was quite upset when I gave him the news. I guess my 13-14 year old self saw things in a rather distorted manner.