I think overall, men probably do move a bit differently to men, because of different pelvis shapes; as with average heights or foot size or whatever, this tells you nothing about an individual.
I'm not sure how important always is to know someone's sex. I've had colleagues, particularly in Asia, I don't have the linguistic background to know if their name is likely to be male or female. I've never met them in person, they don't have photos on their internal profiles, and timezones mean communication is generally by email, so I've not heard their voices. But what matters is not whether they're male or female but whether they can check a cable in a dstacentre (or whatever.) If I need to refer to them, such as in a ticket update, I either repeat their name or use "they".
Because we have a gendered language, at least in terms of third person singular pronouns, we set a lot of store in being able to identify whether people are male or female, but this also leads to other assumptions about people, and it's not always a good thing. There are some languages which don't use gender like this with pronouns, but there aren't many - and I wouldn't suggest using "it", whuch is why there's all the alternative pronous like ze and stuff, but anyone trying to insist on those just brings a whole other load of assumptions about how they think, which in some ways is a shame - it was a good idea if it had come about without all the ideology.
I bet in languages where it's not gendered like this, they still know who is male and female most of the time, though.