This is more of a sound bite than a substantive argument because we can consider natural disease, biology research, aliens, climate, supernovae, asteroids and what not as threats to _all_ humans. Literally nothing is being done about any of these but AI can actually help with all of them.

On the other hand, "AI killing _all_ humans" is the least likely event compared to those listed above. Of course, of you build or operate a nuke plant the wrong way, or a car for that matter, disaster will follow, but AI is much easier to secure than a nuke plant or even a car - a lot easier. "A dangerous token generator" is just an extremely dumb attempt at deception.