Of course PCs come into it but if there is a known latent system failure it should be designed out.
Just saying lack of PCs caused this incident isn’t going to stop it from happening again.
If the AP didn’t disconnect upon selection of TOGA then this incident would not have happened and the next incident of this kind that surely will happen, won’t.
This would not have happened to a 747,757,767,777 or 787 but they all too have their idiosyncrasies.