According to rainboe the B systems are correct and the the pilots should have acted prevent the outcome. However I would not be surprised if the final report will include a request to B to modify the existing system design to alert/avoid the contributory cause to this accident.
I am still do not understand why the A/P have independent feedback from RA, while the A/T have only and always the feedback from RA1. I am not a pilot, but a former system designer, and the only answer to such design (two feedback for A/P and only one for A/T) is to save money. Other reason was to avoid further testing as a new design. I am not saying that better automation would have save the day, but looking at such design I can see many flaws that could be avoided.
FSLF