There is no doubt that the PIC has final responsiblity for the safety of a flight.
However, every other human element in the system also have certain responsibilities.
Incident and accident investigations are supposed to establish the facts and lead us towards a position where the probability of such an incident / accident happening again are reduced.
The PIC is this case is not going to have the chance to make decisions that kill others as well as themselves again.
However, the peole who had operational control of the flights are still round. One should not seek to simply blame people for tragic outcomes but should seek to ensure that they receive further training, testing and if necessary sanction to ensure that they do not contribute to another incident / accident.
To fail to do so would be to simply say that encouraging another PIC to make the same error is acceptable. - Is it?
Regards,
DFC