One of the hallmarks of humanity is that we innovate and adapt. Shutting down / destroying that innovation is a brute force approach that has failed time and time and time and time again in our history. If you ban or destroy technology, it just means someone will do the same thing in private. Even something universally "awful" like nuclear weapons which I think we can all agree should not be used still contributed to our collective knowledge and technological innovations.
So yes, there will be "bad" AI and AI will be used for bad things. But we'll innovate and develop countermeasures, and along the way I'm certain good things will come of it.