It’s based on an old illustration made by someone who wasn’t there misinterpreting the account of a survivor. It took a description of the superstructure buckling upwards at the point of the break and drew it as the entire other half of the ship pivoting upwards

Basically the idea is that the ship didn’t angle down into the water before breaking but instead stayed level until the hull broke at which point both bow and stern pointed up before sinking

You may notice that there is no evidence for this and also it makes approximately negative sense

Okay but consider the following