Is that meaningfully different? If you read malfist's point as "tptacek's point isn't valuable because it's from some random person on the internet" then the problem is "random person on the internet" = "unknown credentials". In group, out group, notoriety, points, whatever are not the issue.

I'll put it this way, I don't give a shit about Robert Downy Jr's opinion on AI technology. His notoriety "means nothing to anybody". But instead, I sure do care about Hinton's (even if I disagree with him).

malfist asked why they should care. You said points. You should have said "tptacek is known to do security work, see his profile". Done. Much more direct. Answers the actual question. Instead you pointed to points, which only makes him "not a stranger" at best but still doesn't answer the question. Intended or not "you should believe tptacek because he has a lot of points" is a reasonable interpretation of what you said.