Personally I don't care/mind. I've been in situations where a guy I happen to be playing with would have a female character but I never gave it much thought as it really doesn't seem like a significant thing in any way. It's fine to play as whatever character you feel comfy/happy playing with.

Also despite being a girl, I also tend to choose male characters to play as whenever it's possible so it would be quite silly and hypocritical of me to have an issue when it's the other way around :)