Shut up, Gringo!
We have EGPWS but operate to strips not in the database, when it ends up inhibited just when you might need it most!
There is no system available or dreamt of that can prevent this sort of accident, in my opinion.
Anyone else remember the story about "Shut up, Gringo!"? Some Spanish-speaking airliner crew called their GPWS "Gringo" because the warnings came in English. So one day it was saying, "Pull UP! Pull UP!" with the crew saying, "Shut up, Gringo!" until the CVR recording suddenly stopped with the sound of an impact!
Given that I am still wasting oxygen I haven't been quite where this accident crew ended up but I have been very, very close, as have many of us who fly in Africa. There's not much point to getting into a huge bitch-fest trying to second-guess or else defend the crew when a CFIT is pretty obviously some sort of big but unrepeatable mistake. Why not just take this as a strong hint to think, "Well, if it happened to those guys it could happen to me. Is there something in the way I operate that I might need to sit down and think about?"
Just off the top of my head I can think of three CFITs with people I knew personally. Two of them now get their mail delivered by groundhogs.
The third guy scattered a Cessna 441 across a maize field and lived to tell the tale. I flew with him for a while post-accident trying to get him back up to speed but he was always kind of a nervous pilot...