If you take out the Jack/Rose love story and add some of the Californian’s scenes and a bit in the wireless room, you could edit Cameron’s Titanic down to a pretty good remake of A Night to Remember. He was clearly influenced by it, some scenes are lifted straight from the ANtR narrative even though they are known to be inaccurate (Andrews in the first class smoking room, Smith on the bridge as the ship goes down come to mind).
I like the Cameron Titanic, actually. The love story notwithstanding, it’s well worth watching for his attention to detail. The reconstruction of the ship was meticulous, and with a few notable exceptions for dramatic license, the account of the sinking is quite accurate (for the information we had at the time - we now know the breakup is incorrect, but at the time it was the best theory) and contains quite a few easter eggs for Titanic nerds. (like me)
That said… I love A Night to Remember and watch it every year on the anniversary of the sinking. The book is well worth reading, too. Walter Lord assembled his narrative based on correspondence with as many survivors as he could reach - often verbatim as they told it, and it’s really a riveting read.
Cameron tested this. There was room for both on the door, but only in a very specific orientation could they both stay dry. And because she was wearing more clothes than he was, even if Jack makes it out of the water, he’s still hypothermic and won’t survive.
Edit: It’s a NatGeo doc called “Titanic: 25 years later.” They’re in a pool that’s 56 degrees F. You can find it on streaming someplace, but here’s a clip. https://www.youtube.com/watch?v=YEJph0aIP-U