There is a massive difference between "there are a few thousand people in the world who might have the specialized knowledge to kill billions" and "anyone with a handful of GPUs or access to a handful of cloud systems could have a conversation with LatestAIUnlimited-900T and make a few specialized mail orders".

The Venn diagram of "people who could arrange to kill most of humanity without being stopped" and "people who want to kill most of humanity" is thankfully the empty set. If the former set expands to millions of people, that may not remain true.