This is a perfect example of an ad hominem attack which adds little to the discourse: https://yourlogicalfallacyis.com/ad-hominem

The comment I was replying to was also using the fact that mjg is a specific person who knew Stallman as a reason they are credible. When the thing being discussed is how reliable someone is at conveying private information they have, rather than them making some argument devoid of experience, ad hom is not a fallacy.

That’s not how your comment reads. It reads as “well, we know how he feels, so keep that in mind.” Which, is an ad hominem attack.

If you didn’t mean it that way, than please consider that your word choices come across as mocking, which changes the received meaning.

It absolutely is an ad hom, I'm just claiming that that is not a fallacy in this case, since the trustworthiness or bias of the dude is the thing we are discussing. Ad hom isn't always a fallacy. Nobody has even discussed any arguments coming from mjg, they're just chalking him up on a tally of who is on whose side. And I think the dude is super biased, and that whose side he is on isn't evidence of anything since he picks sides based on ideology, not on a case-by-case basis.