As I understood flying all these years manual flying you make things happen, auto flight watch the things you want happen. Nobody puts AP on and goes to sleep. How can you not monitor speed? Auotomation does not mean you don't scan. SFO type incidents cannot happen in isolation. These are examples of pilots slowly loosing their scan over the years. Other than manual control inputs everything else remains same. Unless offcourse there was extreme fatigue and sleepiness then anything is possible.