I don't believe that accidents such as this are due to a single factor, but a series of failures...
There was a training issue at fault at AA for rudder input, but if Airbus was aware that excessive rudder input could cause structural failure, do they not have an obligation to modify systems to compensate? Dampen rudder input at higher speeds as to avoid this very situation from taking place?
(Not taking sides, just trying to take an objective viewpoint)