Weren't there a whole lot of things that contributed, including -
Quality control issues with both the steel plating and the rivets: if the steel had been a bit less rigid, the iceberg collision would just have dented the starboard bow, rather than opening the seam; if stronger rivets had been used (more expensive) they might have held even in the actual circumstances.
Failure of lookouts to see the iceberg soon enough: the lookouts weren't using binoculars. There was apparently a set available for the masthead lookouts - in a locked cabinet in the lookout post, but the key had inadvertently been retained by a junior navigating officer transferred off the ship when the arrival of Chief Officer Wilde (who was senior to Murdoch, original Chief Officer) from Olympic caused the entire navigation officer team to be bumped down a place in the hierarchy with the original Fifth Officer losing his berth entirely.