Stephan:
As stated by others, a machine would have landed in the only available open area - the Hudson River. But unlike a human pilot, a machine could do it at night, in zero-zero conditions.
As for envisioning every circumstance or failure… Humans can’t do that, either. But neither humans nor machines NEED to do that. Impediments-to-safety happen on an ad-hoc basis. Mitigations are employed on an ad hoc basis. Machines can address thousands of failures simultaneously; humans cannot.
The ego-rupturing truth is that flying just isn’t all that complicated, when compared to many other jobs that computers do successfully, every day.