If it really wasn't even an issue, this wouldn't be coming up as often as it does, though, would it? To me, "if someone tells you they prefer singular 'they', use that" is non-controversial, just like "if someone tells you they go by 'Goldie,' use that" should be. Insisting "No, I am going to call you by the pronouns I believe are 'correct' for you" is akin to "No, your legal name is 'Marigold,' and I am going to call you 'Mary.'" Insisting that you will not, under any circumstances, call a person what they've requested you call them is -- to me -- pretty clearly being a discourteous jerk.
There are a lot of valid complaints about the way Stack Overflow moderates in general, but I don't get the impression that this particular squabble is over moderation practices -- it seems to be about upcoming changes to SO's Code of Conduct. I don't know what those changes are, so I'll reserve judgement. I am certainly hoping that it doesn't boil down to "I cannot abide being required to refer to transgender women with 'her' and 'she'," though.