I don't think the Aum case points the way you're describing: they used a non-pathogenic strain of anthrax because they didn't know any better. That's a knowledge failure.
But even then, the debate isn't about whether open weight bioweapons exist today: it's about whether they will exist in the future. I think Amodei's argument here makes a lot of sense: "what I believe currently keeps us safe in biology is not 'defenders', or even the availability of materials, but a negative correlation between intellectual capability and desire to commit catastrophic harm. Previous technologies like internet search or even DNA synthesis were nowhere near powerful enough to break this correlation, but I worry that at its current rate of progress, AI will do so very soon."
(I'm not just spouting off; I put my time where my mouth is. I used to work in big tech, but I left for a much less well-paying job building an early-warning system for engineered pandemics.)
> I don't think the Aum case points the way you're describing: they used a non-pathogenic strain of anthrax because they didn't know any better. That's a knowledge failure.
No, check https://en.wikipedia.org/wiki/Matsumoto_sarin_attack
There are a lot of interviews with former cult members around. They had armed helicopters, a testing station in western Australia, produced piles of sarin. This wasn't a lack of science knowledge that screwed them up, they notoriously involved the elite class of Japan - it was a whole other category.
There is no link between AI and bioweapons that makes this stuff any more reasonable than availability of detailed descriptions of nuclear reactors enables us to be purifying weapons grade plutonium in our yards.