In this scenario, at most a few hundred strong dudes might survive, and still it was a major disaster. More people could have participated in the enquiries, and more accurate picture might have been revealed well before 1985, as many survivors at the stern would have experienced the break-up. Even though most people would have died, the gentler sinking of the stern would perhaps make more floating corpses to be recovered, not mentioning that the later sinking time would make corpses less dispersed. Imagine crews in Capathia witnessing directly the fate of the people climbing on a slowly-sinking stern. Also imagine the crews witnessing hundreds of corpses like what Lowe saw in when #14 returned to the site. The scene must be shocking!
The fate of engine room and lower portion of the stern could have been revealed, as a slower sinking pace would allow some, if not injured, to escape the superstructure by slowly climbing the ladders after the stern settled to its metastable position.
Engineers MIGHT have some thought, inspiring to the metastable status of the stern. They might have suggested after the disaster that, instead of putting enough lifeboats, the bow and the stern should be made detachable mechanically, under command of captains when the remaining parts of the ship could be saved by detaching the fatal part. (Similar removing the parts affected by cancer by surgery, and saving the patient)