It would have helped me avoid a lot of confusion, conflict, and awkwardness growing up. I was always nonbinary. I just didn't have the language to talk about how I was feeling. Finally encountering other people whose specific experience matched mine in the 2010s was eye-opening.
Not only can you be something other than two possibilities, there's a whole space of possibilities inside, outside, and around them! Amazing. I needed that when I was 5.