There are plenty of physical and legal barriers to creating a bioweapon and that's not going to change if everyone becomes smarter with AI. And even if we really somehow end up in a world where everyone has a lab at home and people can easily create viruses, they can also easily create vaccines and anti-virals. The advancements in medicine will outpace bioweapons by a lot because most people are afraid of bioweapons.

Intelligence itself is not dangerous unless only a few orgs control it and it's aligned to those orgs' values rather than human values. The safety narrative is just "intelligence for me, but not for thee" in disguise.