A 145mm Ww inner bulkhead as opposed to the 45mm Ww bulkhead may have helped stop the splinters, but the question remains what the side effects would have been in terms of protection from torpedoes and mines.
The 110 mm protective plating of the rudder compartment completely withstood the explosive effect of the rudder hit and remain watertight despite large destructive effect to the rooms within that compartment. Despite comparatively close proximity to the detonation site.
same can be found for North Carolina
in this case the 95mm inner citadel around the magazines completely withstood the explosive effect of a torpedo hit, maybe this was the lucky fact in NCs history.