The post would be a lot clearer if it had a motivating example that really did have bad consequences, ask things considered.
The extreme case would be a scientific discovery which enabled anyone to destroy the world, such as the supernova thing in Three Worlds Collide or the thought experiment that Bostrom discusses in The Vulnerable World Hypothesis:
So let us consider a counterfactual history in which Szilard invents nuclear fission and realizes that a nuclear bomb could be made with a piece of glass, a metal object, and a battery arranged in a particular configuration. What happens next? Szilard becomes gravely concerned. He sees that his discovery must be kept secret at all costs. But how. His insight is bound to occur to others. He could talk to a few of his physicist friends, the ones most likely to stumble upon the idea, and try to persuade them not to publish anything on nuclear chain reactions or on any of the reasoning steps leading up to the dangerous discovery. (That is what Szilard did in actual history.)
[...] Soon, figuring out how to initiate a nuclear chain reaction with pieces of metal, glass, and electricity will no longer take genius but will be within reach of any STEM student with an inventive mindset.
The extreme case would be a scientific discovery which enabled anyone to destroy the world, such as the supernova thing in Three Worlds Collide or the thought experiment that Bostrom discusses in The Vulnerable World Hypothesis: