For most "doom" scenarios require only weaker assumption: AIs need to be goal seeking. If they can make decisions and take actions to achieve goals it is possible those goals will be malaligned.
The line between "the ability to make good decisions" and a "goal" seems pretty thin to me.
Now, I think you need more than goal, you also need some creativity and maybe even deviousness to become a real threat (in the sense that we would probably detect naive malalignment). But I'm not sure about this, there are other ways that we could have complex-system failures that go unobserved.