Generalizations are fun, but they don't make the greatest arguments.

Not all users that were upset at the /r/fatpeoplehate ban were subscribers to that sub, and not all subscribers to that sub were partaking in harassment I presume (which is a reasonable assessment based on the subscriber numbers and the usual ratios of participation in online communities).

So taking all that into account, even if this is in fact the main demographic of disgruntled users, that still has nothing to do with misogyny. If it were true misogyny, they likely wouldn't even be using a female employee as their martyr. I really don't understand what distorting contexts and stretching the truth to frame things in terms of sexism is supposed to accomplish, but it's certainly not proving any points.

Reddit screwed up, and it's CEO's decisions clearly affected an influential and vocal part of the community, to the point where it's now open to competition from sites like voat. There's enough business mishaps and silliness in all this to explain everything, I don't see how shoehorning misogyny into it adds anything of value.