...but LLMs do know how; they can design and order one, or tell you how to build a lab to make one. If you ignore this option, you are simply lacking imagination.
Yes, terrible stuff happens, but they are extreme outliers. Not sure how this works, but we can trust strangers to quite a high degree.
I have no experience in the matter, but surely designing viruses is not a simple affair. (In any profession, having a blueprint is not the same as having knowledge, equipment and practical experience; if somebody would try, my bet would be that they would die during early stages of the process, due to inexperience of handling hazardous materials; kind of like Mr Darwin looks after us)
I assume virus creation is more like building a house. It involves physical work and chemical reactions that need time to finish in correct order. Each attempt costs a LOT more of time&money and involves actual risks.
The reason we dont see any serious attempts to create a deadly pandemic is not that we keep insane people out of labs, because there is no way to find out if someone is a cultist or murderous psycho when they have every reason to actively hide it. Its because a) most people are not evil and b) a virus that can kill everyone it touches would probably kill its creator first.
As someone with basically zero bio experience I think I could get a working smallpox or ebola level virus in a year or two if I had time to learn, lab equipment and Annas Library. No LLMs needed. But I dont want to do that, and I think its the same for all the people who could do it right now.