No, they're warning us about an AI which could outsmart or outperform us, and lead to our demise as it pursues the goals we've encoded into it without realizing they lead to a result we don't want.
I don't think so. I think a case can be made that he's talking less about SkyNet and more about the risks something like an automated trading algorithm (or planning system, or any case where we put too much trust in a system as infallible) ten years in the future causing major disruption due to too much trust in a fallible system as being infallible.
There's also the possibility that a true AI (not just a complex expert system as above) may be fallible just like a person in not being able to correctly account for the unknown unknowns.
In the end I think it's about the difference between automating positions to make them more efficient (meaning it's still possible to do manually but less efficiently) and relying on things that are essentially impossible to do manually, such as an economic planning AI which may outperform regular economists 95% of the time. The question is what happens in that 5%, and will it catch the problem, and if not, will we keep listening to it as it takes us down a dangerous path.