It doesn't even need to go that far. We could and should tweak them until they do benefit us. But yes, if that becomes impossible, then obviously they shouldn't exist. I don't think we're there yet.
Still, the notion should be that they're tools to benefit society. When a tool no longer benefits you, you don't use it anymore.
Yeah, I think we are still a long ways off, I was just being frank about what they are, and how we should treat them. We don't have to be concerned for their well being or existence, since they are only a means to an end. When we have a better method of getting to that end, we should not hesitate.