I find this hard to believe assuming we're talking about English here. Yesterday in a meeting somebody referred to me with a pronoun while speaking to the group. And I'm confident that other people use pronouns about me pretty regularly, in that I do that frequently about them.
If you're saying you personally don't care what gender you get referred to as, that's your right. But for other people getting misgendered can be a significant problem. If you want to change that, it's not those people you need to get to change. It's the ones making such a big deal about other people's gender.
First of all the world of online is different than the real world, where there's no parentheses or tags floating next to you. Meaning new people you've just met in a meeting, say, have no idea what the pronouns are.
If they're out of the norm then it may make sense to mention it then, I don't think society is hostile to it. I believe it applies to less than one percent of the US population, so it seems excessive to establish a norm of behavior for all, since harmony seems achievable despite that.
If you're saying you personally don't care what gender you get referred to as, that's your right. But for other people getting misgendered can be a significant problem. If you want to change that, it's not those people you need to get to change. It's the ones making such a big deal about other people's gender.