Points for addressing the title. And in all honesty I don't know. Usually thirsty guys keep girls in fireteams, but every once in awhile I'll hear guys think that girls have worse gunskill or something like that. The most sexist thing I've seen in destiny was when I was running the kings fall with two girls that were (at the time) just joking around. They were close friends, most everyone in the fireteam knew eachother. The rest of us were just quiet and laughing along but looking for our final person to raid with. The final person we invited was quiet, but was rather controlling. He seemed frustrated for some reason with the two girls. In the middle between wipes he blurted out "Who put two girls together in the same party?" or something along those lines. There was a silence. I cut the silence by just trying to say what we should do to not wipe again, and from then on there was just a disturbing silence. We restarted the encounter, and we ended up wiping again (can't remember why) and that guy decided to blame it on all of us. It was something like "The -blam!- is your guys's problem? Why would -" that's when he got the boot.