I don't see why this has to be an either/or proposition. There are times when a computer is better suited to a particular task and times when a human pilot with full control of the aircraft is better suited to a set of tasks that fall outside what the programmers envisioned. Humans make mistakes, but they also are capable of doing things right when things really hit the fan. There is no computer on Earth capable of what doing what Al Haynes and crew did with UA 232 or what that Aloha crew did with their 737 when the roof came off. On the other side, TCAS, windshear detection and GPWS have been quantum leaps forward in making aviation safer, though those systems still require a human pilot to intervene.
I'd like to address this point because it is based upon what is a common yet faulty understanding of the nature of computer systems software. All software design is a function of collective experience. This collective experience can come through user studies, trial and error, or even by tombstone. It remains a repository of collective experience.
Experience is not infinite. While there are indeed millions of possible permutations at the interface of weather, the physics of flight, passenger comfort, and regulatory frameworks these combinations are finite. Moreover, most of them are not deadly. There is only a small subset, perhaps in the hundreds of thousands, that result in a plane crashing. The result is that the collective experience as codified in software will always and inevitably surpass that of a single human mind. There is only one possible exception to that rule and that is if the person under discussion is omniscient and omnipotent--that is God. No human pilot is God.
So while it is true that that there remains limitations to computer software today evey accident just moves the needle one more degree closer to full. Eventually every possible permutations will be coded for. Indeed, there is a cogent case that right now that human pilots cause more crashes than they prevent. But whether that is true this exact second in time is irrelevant to the fact that the day is approaching.