Ok. Let’s start.
You (and others) read Derior’s messages and thought they were polite.
I (and others) read Derior’s messages and though they were condescending.
Text being what it is, and the large groups on either side, I think we can fairly say that a reasonable person could read it either way.
I’m going to pause for a moment though, and explain why it reads to me as condescending.
Derior is an enthusiast. Not an expert in the field. And yet, in his self-described attempt to have a discussion with an expert, he started by making an argument, rather than asking a question. Had he said something like “Can you talk about branching dialog? What are the issues with that that would keep it from addressing this problem in an MMO?” I think we would not be having this discussion at all. But what he did was exactly what she actually accused him of, being a layman lecturing a professional on their area of expertise.
The question then becomes why? Are we looking at the unfortunately common “enthusiast entitlement” which leads people (sadly especially in areas of mass media) to have an exaggerated opinion of their own expertise? Are we looking at someone who for other reasons (possibly even not at the conscious level) will try to position them-self as a peer or colleague in any discussion, even when they haven’t earned that role and do not have the knowledge to back it up? Or are we looking at misogyny (again, conscious or not, everyone has biases) where we have a male enthusiast who at some level thinks that the combination of gender and hobby implicitly makes him a peer of any female developer?
Honestly, no clue. All of them are actually possible, which is why I think that drawing the final conclusion is not inherently unreasonable.
At the core, he absolutely did what she accused him of. He, who has never made games, was in fact trying to tell someone who did it for a living how they should do their job.
Now, the next question is, is it fair to read a male enthusiast doing that as doing it because of her gender. That is, would he have done it to a male developer? While we cannot say for sure about him, we absolutely can say that this lecturing problem seems to be far more likely to be aimed at female developers than at male developers.
Moreover, communications don’t happen in a vacuum. There are plenty of phrases and patterns in English which have been used so often as micro-aggressions (or even aggression aggessions) or to signal prejuidice to like-minded people that they themselves become problematic.
So, is Derior misogynist? If you made me actually have to pick one way or another, I’d probably go with “entitled with an exaggerated self-opinion of his expertise” rather than misogynistic. I just think that reasonable people could read that pattern the other way.