AbA: That is true of many people, but there are definitely some genetically wired to only be attracted to men.
On the general issue, I can definitely hear open but not-practicing people wanting to get away from attacking eyes. Then again, I don’t know if a Minyan exists of open but not-practicing people attracted to the same gender (I have met a few, though, so maybe there are10 of them around the world). But calling it “Pride” and including the “B” and “T” parts of those sheds light on what the Minyan is trying to accomplish and it seems to be accommodating far more than just Shomrei Torah Umitzvos with a certain Yetzer Hara.