"Back in the 1960s after the moon landings, people would have expected we would be well past Mars by now. Probably Jupiter, Saturn or other stars."
Your example and the frequently quoted one about flying cars is the wrong analogy to make. There's a reason to be more optimistic, or pessimistic (depending on whether you view machine intelligence as threat), with regard the progress of AI.
Up until now, nobody has been mass producing man-rated spaceships, or flying cars and warp drives for that matter. On the other hand, computers and computer parts have been mass-produced since shortly after Jack Kilby invented the transistor. This is the reason for the so-called Moore's Law.
Now, unless you can prove that the very idea of AI is impossible, then the development of increasingly powerful computers as an aftereffect of Moore's Law and similar technologies (massively parallel computing etc) will result in systems exponentially more powerful than IBM's Watson. At some point a future Watson or Google AI system will make "decisions" indistinguishable from a human's.
Now, if Boeing and others are mass producing rocket parts at the same volume that Ford, Toyota, and their suppliers, etc are producing automobile parts (or Samsung and Foxconn smartphone parts), I'd say we'd not only be on Mars right now, we'd have a space colony on Pluto, if that's an interesting enough minor planet.