IDK what you mean with "speak for yourself" (don't we always speak for ourselves? :S)
Just to clarify, i think it's better to use gender-neutral pronouns when gender is irrelevant, or unknown. And it's easy! I've been doing so writing on English online forums since more 2 decades ago.
But i don't think it's reasonable to get mad at someone, or even attack them, for using male pronouns instead of gender-neutral ones. It doesn't say anything about the person being sexist or hateful. The veeery vast majority of people who do this do it out of ignorance rather than malice. And attacking someone for something they don't even consider as a moral choice —like referring to a generic programmer a "he" instead of "they"— does nothing positive for this world, on the contrary.
It's a one-time error the maintainer made 3 years ago (at a time when much of the US-influenced west was going crazy with polarization over the use of pronouns), not a consistent behavior of intolerance as one would expect given the level of hostility towards the project seen here. I personally find it weirder to hold such a long-standing grudge for a one-off error, and over a project one is not even personally involved with.
it’s not a meme unless it goes viral.
If you want to be pedantic, it'd be good to know that that's not what a meme is. A meme is a unit of cultural information—analogous to a gene being a unit of genetic information. A meme may not go viral, just like a gene might not be successfully copied onto other generations, but it's still a meme nonetheless :)