Machinbird
Do you really want your trim system quietly doing things behind your back? (Actually out of the range of your normal scan).
Although that question is not pointed at me, i like to comment on it.
The whole FBW-system as it is designed would not work without autotrim. Fundamentally nothing is wrong with it except the point when part of the FBW logic goes down the train. At that point the system should be at least as easy to understand and be as easy to fly as a normal conventional system.
In the case we discuss here the system is excellent and far better than a conventional design when everything is online and it gets a lot more difficult when part of the system goes offline.
Holding the stick back in a stuation where the aerodynamic performance of the aircraft does not allow further pitchup due to missing lifties would leave the trim in a conventional aircraft unattended , but caused an unnecessary full NU trim state in the case of AF447.
Whoever thinks, that this built in system function is a clever design should reconsider.