The Air France example is not a good one - there's no indication the pilots didn't hear or heed the warning, it's that a loud voice blaring "STALL!" was only on

The Air France example is not a good one - there's no indication the pilots didn't hear or heed the warning, it's that a loud voice blaring "STALL!" was only one of multiple "pay attention to me now" things in the cockpit. To claim the alert needs to be more noticeable/annoying/loud/whatever is completely wrong - they needed information, not alerts.