1. people bringing up how they "don't feel the need to tell everyone" that they're straight forget that they can tell everyone that they're straight with no repercussions, and additionally, most people already assume that they are straight. OP is most likely being open about their sexuality the same as any straight person and is getting harassed for it, which is, as sonic would say, no good.
2. The reason you give for being fine with people having to hide that they're gay is that, if I understand the strangely worded story correctly, a gay person was flirting with you and took it badly when you rejected them. This seems unrelated.
3. There have always been cultures with more than two genders, it's just not a northern European thing so no one acknowledges it.
Edit: oh also, people are talking about biological genders in the replies, that's an oxymoron. Gender is related to presentation and inherently cannot be a biologic trait. They're thinking of sex, which I guess is limited to two biological states if you don't include intersex people.
