I just think that it is very hard to understand the scientific consensus (average view of people who spend a lot of time thinking about this) when all you read are popular science articles that tend to focus on the exciting/new/possibly game changing edges. I'm just here letting people know what the consensus is.
Framing it as a result that flies in the face of consensus is fun and exciting, especially since people who are science-literate know that a single compelling result can overturn a consensus formed by a large body of previous work. But framing it in that sense is unhelpful, since the vast majority of publications that “fly in the face of consensus” do not. It’s a lot less exciting to view this as one more paper on a large pile supporting MOND, that is still small in comparison to the pile that support dark matter. The paper is obviously worthy of attention and isn’t being dismissed out of hand, it is published in The Astrophysical Journal. But would Hacker News be discussing it if not for the contrarianism embodied by the former framing, as opposed to the latter?
"The ________ theory/hypothesis is fringe, the consensus is ________" is argument by authority.
See the difference? Phrasing matters in this case. All too often it is phrased the second way. I don't expect someone to literally enumerate all the evidence for or against something, but there is a middle ground between that and just saying "well consensus is ______".
That is not an argument, so it can't be "argument by authority." It is a framing.
That's exactly what it is. The rest of your argument boils down to, "if a lot of prominent people in a field believe something, it must be because there is a lot of merit-based evidence". That assertion is completely false. Merit-based evidence is one of the ingredients that lead to consensus, but hardly the only one.
It's not, because is specifically argument based on authority. Consensus could have authority in democratic context, but that isn't the meaning of "argument by <X>" which is the distilled context of some basis of proof. You could just as easily link consensus to "Argumentum ad populum".
In fact, this is spelled out on wikipedia: The two are similar, but not the same - both are "Fallacies of relevance": https://en.wikipedia.org/wiki/Argumentum_ad_populum
This doesn't really apply either though, because we are talking consensus among a specialized group of experts/peers, which seems to me a lot more relevant that general consensus. Appeal to authority isn't always fallicious: https://en.wikipedia.org/wiki/Argument_from_authority