/s?

GP's point (and I agree) is that an evil actor could, in principle, do those things already (and a much more intelligent one, while we're at it).

And yet, it doesn't happen. Why? Because reality is not a "winner takes all" game. Actions carry consequences and other factors limit the extent of damage any actor could do.

It is way more threatening to human life that there exists, today, a huge stockpile of nuclear weapons all around the world.