Consciousness and questions of consciousness in my opinion don't matter for discussion of the safety of AI. An AI which is rogue and dangerous can easily be developed using current technology. A smart contract could easily be harmful to humanity using only current technology. The smart contract doesn't have to have consciousness to invent a language we cannot understand and begin harming humans. It simply would have to be programmed in a really bad way to allow it to evolve such a capability.

In other words the AI would have to be amoral. Amoral autonomous agents present this risk. Amoral smart contracts can evolve into this.