Hmm, maybe I need to watch dirty pair, lol.

My 100% vibes based analysis is that 0.5-1% and 3% are both low. Both for the reasons you mentioned, but also because I feel like in a more open society there would be a lot more agender, non-binary (non-trinary? for societies with a 3rd gender), people doing thier own gender, etc. Like even in a society with a third gender, while that's better than just two, there is still a lot of pressure to be one of those three, yeah? In guess I feel like too many studies shit trans people still are too binary focused. But idk. Do you work in stats? You probably know more on this than me