Did he? I only saw him point to the rule against politics.

He should have said it's because the PR isn't worth the time, but it also seems motivated by something that's against the rules (i.e. why make a PR that only fixes gender in one comment? There was a later PR that was accepted that fixed it in several places).

So without more evidence, I cannot say what the dev's motivations for rejecting the PR were, aside from the apparent rule breakage mentioned. They didn't say they disagreed with the change (i.e. that the change was wrong), just the proposal of the change (i.e. seems more motivated by virtue signaling instead of improving the dev experience). And you can look at the comments and see justification for that position, since it quickly devolved into actual politics with people accusing the dev of being a Nazi.

Maybe if you showed a pattern across more than just this incident (i.e. over months or years), but this sounds more like people being stubborn than tolerant.