It's not obvious to me that knowing everyone's gender at all times is important. In fact, as you say, there's a variety of languages where that isn't the case.

It's not obvious to me that knowing everyone's gender at all times is important. In fact, as you say, there's a variety of languages where that isn't the case. When I'm talking about someone I bumped into on the bus, why is it relevant what gender they are above pretty much anything else you could choose to encode there? I'd much prefer to encode, for example, my relationship with them - whether I'm close to them or not, whether I see them as equal, inferior or superior. Gender is mostly a thing that becomes relevant when talking about relationships and sex or healthcare, and even then not always.