The AI systems we are talking about are not self modifying code. They are llm. Large language models. There is a model that is a condensed essence of the training data and that so called large language model is capable of creating a response to a prompt. That can be applied to images as well. Obtaining the training data and using the works of such systems is critizised under ethical aspects, therefore the "evil" aspect.
But maybe you were talking about self driving cars.