Speaking just for myself, it's not like I underline my sex with every comment I make. If I cared about people knowing it all the time I'd have put (she/her) in my username or something.
I usually make a point out of mentioning my sex when I talk about my personal history though, as is the case with my
reply to
SearingFive. Seems that the sex of the respondent might matter in that case. The "benefit," if you will, is that people won't assume I'm a gay man when talking about romance and sex with men or male characters, so the conversation can flow normally.
As for assuming it's a lie, it's not like it changes a whole lot to discussing the game. I can't force people to accept that I am who I claim to be.