As it stands now, I think the paper raises important questions, but unfortunately provides quite often a superficial response. And I wish the various arguments presented here could be refined.
Generally, I recommend you speak more about the broader consequence of scientific censorship. For instance, we do want to avoid eco-chamber situations (think about Twitter/X losing some left-wing users due to the algorithm seemingly promoting right-wing pro articles and the feeling of some people that Elon Musk is applying some sort of sneaky censorship). There are some studies showing that reviewers are not neutral and their conclusion on a paper reflects their own biases and preferences. This could be worth citing, as it would indicate this problem is more prevalent if censorship is widespread because it will reduce the number of reviewers having dissenting views. You can also say that publication bias and replication crisis are pervasive, and censorship of dissenting views will make the situation even worse. Those are just some ideas on how I would tackle this problem.
You wrote:
Take Bird et al.’s use of selective citation and strawman
I suggest you provide some evidence of it, either in the main text or in a footnote.
You write
I also suspect the study’s authors would be lauded with merit pay and promotion, rather than the revocation of their tenure.
This is interesting, but again it will be way more convincing if you can develop further. To give you some ideas, let’s consider this paragraph from Carroll’s book, Literary Darwinism, chapter 2, Modern Darwinism and the Pseudo-Revolutions of Stephen Jay Gould. Somewhere, he wrote:
Alcock and Pinker both believe in the ultimate integrity of the scientific process. On the basis of this belief, Alcock declares, “I am confident that, in the long run, Gould’s polemical essays will be just an odd footnote in the history of evolutionary thought, a history that has been shaped in a wonderfully productive manner by the adaptationist perspective” (p. 335). Gould’s situation is something like that in the story of the man, hungry for fame, who made a particularly ingenious bargain with the devil—ingenious, that is, on the devil’s side. In return for his soul, the man would be famous in his own day, but only on the condition that after his death all trace of his works would be eradicated from the memory of men.
If I had to answer Bird, Jackson & Winston, I would be asking whether honesty and courage should not be lauded as well, even at the cost of becoming public enemy number 1. One could say it is easy to seek fame and public love, but much harder to stay true and being hated for it. One could further ask whether truthfulness is necessarily incompatible with peace in the case of hereditarianism.
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Bird et al. paint “hereditarians” as ham-fisted incompetents who may also be accessories to mass murder. They do so with the ironic claim that our research is not “value neutral.”
I recommend you address this point directly because this would help bolster your own case against academic censorship. Let's use a different perspective. You are the director of a supermarket, but your fish sector makes no money. Worse, it makes you lose some money. Closing it would be a bad idea, because when customers go to a supermarket, they expect to see all kinds of products being available, at any time. If you close this section, you might end up losing more money due to customers leaving your supermarket for good.
Applying this logic to academic papers, you can say that allowing censorship of dissenting views will undermine all accepted papers because general trustworthiness is no longer valued.
Another way of thinking this problem through is the idea that retweeting is not endorsement. Exposing a provocating tweet will eventually show how people respond and debunk a provocating statement. Generally, it is worth knowing what people think of it. Hiding a problem will not make it go away.
You write:
One thousand words is a harsh limit, and I had hoped to also address Bird et al.’s “race is just a social construct” strawman.
In this case, why not providing a direct answer in your commentary here, in more detail?