I don't know a lot of trans people in real life and I have never miss-gendered someone. But there are a lot of prominent trans people in for example the gaming community and I am basing that anecdote on the discussions from there.

Edit: Note that I am not the person above the parent, I don't think there are any grave consequences for missgendering people, at least not if you don't do it consistently. I guess it could happen if you did it on for example twitter and some activist picked it up, but not in a casual conversation at work.

Late edit: As for what I consider man/woman, take this picture: https://keyassets.timeincuk.net/inspirewp/live/wp-content/up...

If I saw it without context I'd assume it was a guy being surrounded by two women based on their body and face structures, it is very hard to see the middle one as a woman. But surprisingly they are all three women.