Earlier quoted context omitted.
In a sphere where we usually choose our names and expect other people to use them, instead of what's written in some official document, I don't see how chosen pronouns are any different. Honestly, it's not hard to call people what they want to be called. You might feel the line between innocent mistake and maliciousness has not been crossed. Other people do disagree.
The linked blog post says nothing about pronouns specifically, it's making a much broader statement that is clearly nonsense. When you promote putting people on lists, bear in mind that some of us are happy to reciprocate. I certainly wouldn't want to employ someone who thinks "if it offends a trans person, then it is transphobic" is a reasonable maxim.
https://rms-open-letter.github.io/appendix
"RMS has spent years on a campaign against using people’s correct pronouns."
And OP said: "Ah, postmodernism! Where the words are made up, and intent doesn't matter!"
I'm not commenting on RMS's views about what makes consent. And I am not stepping into that discussion. But calling people something different than what they want to be called, is just dickish.