Well put! To piggy back off your point, I think the persistence issue in it's current state is what will ultimately stop it from taking over too many knowledge worker jobs. The efficiency it currently creates for each current knowledge worker will of course be a threat to employment if production doesn't increase as well, but if history is at all trustworthy, production will increase.

I think the biggest issue right now (outside of data storage) for creating AI that is persistent in it's knowledge is the algorithm to receive and accurately weigh new data on the fly. You could say it's the algorithm for wisdom, even.