Obviously only guessing, but I'll bet 100,000 cars have passed that exact spot this year without crashing. And the car looks to be intact from what little we can see (still has 4 wheels).My guess is he was in Race mode and lost the back end, car went sideways and passenger side took the impact of the metal rail . Could have been preventable if he was in Dynamic but its only a guess.
So the overwhelming thought is that it could have been preventable in any mode!
Obviously, we won't have all the information, nor do authorities yet.
Nor does it help the victims. But if it saves a repeat, then it is worthwhile to mention it.