And the other part is simply just ethos, who the author is does change what kind of credibility you will give an argument.
Initially, maybe. It sounds a lot like the comment was arguing that people should do as much as the article's author before they are allowed to "pick it apart". That's lazy thinking to me, "that person has done a lot, don't you dare criticize their article". And that, mind you, before anyone had even pulled apart the point, it's some kind of pre-emptive argument to authority.
In this case, chances are quite good that the author of the article will read the parent comment (and the author has responded to other comments as well)
I don't mind the down votes, I have hidden their effect and all counters to make sure I don't get sad about down votes and don't let my ego get inflated by up votes. Had you not mentioned it, I wouldn't have known, but I'll try to not let it ruin my day ;)
The first part, I believe, is garbage. They might've done a lot or a little for open source, that shouldn't mean their ideas aren't to be criticized or picked apart.