Sully did not need alpha protection to make his Hudson landing. Only a pilot that would stall an aircraft before touchdown would need that. Don't most of us pilots approach a landing surface at 1.3 stall speed, flair to stop descent rate and roll it on with a perfect landing most of the time? We can do it power on or power off, on a runway or on the Hudson. Landing in the Hudson requires judgement on optimum flap setting and deck angle on touchdown with almost zero sink rate. You certainly don't want to be stalled or in a high pitch attitude when the tail hits the water first. Read Sully's book. He never said the Airbus automation helped him in any way and I am sure it didn't. Maybe it would help a mediocre pilot but not Sully. If alpha protection intervened on his Hudson landing the tail was probably already in the river so had no affect on the outcome. He would have never stalled into the Hudson. He was too professional.