If you take into account other engagements like Dogger Bank, and the fact that Hood *had* had her armor scheme improved after Jutland, the probability is even lower.
Well, exactly that construction history is what makes me think that the Hood was doomed in that battle. First of all, her construction was changed after Jutland, but only inconsequential. Her front magazines had their order swapped to the standard of WW2, with the powder handling room below the shell room. But the aft magazines did not get upgraded. Then the front deck armor was upgraded, but the WW1 era misconceptions in deck armor design had not been corrected. And the aft deck armor did not get upgraded at all.
Now, in WW1, the deck armor was flawed, but not yet bad. But in WW2 with against modern shells with delayed aft fuze, this design was not just flawed, it was deadly.
So, once the aft deck armor got exposed directly to 10.5° fire, a very large cross section of vulnerable, not upgraded armor got exposed. Even if the Germans did not know of this weakness and did not try to intentionally exploit it: There had been eight shells in a salvo, the Germans had already a firing solution, so you can be sure a good portion of those eight shells will find the Hood - at least one, maybe even three.
That the Hood was hit at its Achilles Heel on the first salvo fired after the Hood started to turn was maybe luck. But 27 seconds later, the next salvo would have had an even better chance to hit it. Not the Bismarck needed to be lucky, the Hood needed it. And the Hood had no luck.
Would the Hood have received a consequent construction and armor upgrade, history would likely have been different. But it wasn't. The armor would have been vulnerable to plunging fire, but at the distances of the battle of the Denmark Strait, the shells would have arrived at a too shallow angle to be especially dangerous. It could have last much longer. The Germans considered the optimal combat distance for the Bismarck class at about 20 km, this battle was at nearly half the distance, also thanks to Lütjen for refusing to give order to open fire.
Also: The wreckage shows that the Hood was not just dying of one magazine explosion, but multiple. The big one broke its back, but the Cordite was not done yet.