I wish people would stop using ground-based examples of automated control to justify systems for aircraft.
There is one BIG difference. Just about any ground based control system faced with data ‘outside parameters’ will contain Code to ‘halt and call for assistance’. Difficult to do when you are flying!
And for all those second guessing Sully; remember a big part of the decision making was that ‘even with a 90% chance of a successful turn back, there was a 10% chance of a dive into a heavily populated area’. How do Computers/ Programmers deal with that?