why would it be bad

You can't stop scientific progress. Right now some people are worried that there will not be jobs for many people because of automation. They lack vision...as we automate new jobs will be created. The automobile put the horse and buggy out of business...but look what happened. Have faith in human ingenuity.

Automation is neither good nor bad until someone uses it. You may jump to people will not need to direct sentient AI. That is true, and I believe the AI will understand ethics and act accordingly.

Probably has no effect.