How did the writing process between Avatar and Titanic differ?

Despite feeling like a dead franchise for years, Avatar hasn't slowed its financial momentum since its release. Breaking the box office during its initial run, Avatar sat at the top of the cinematic heap until it was briefly usurped by Avengers: Endgame. However, even the combined might of Earth's mightiest heroes could stem the crushing blue wave that was Avatar's dominance as the film clawed it's way back to the top after a rerelease. Avatar's reign is like Thanos. It is inevitable. 

Decades before Avatar, another film reigned as the box office king: Titanic. For those keeping score at home, both films are from the visionary mind of James Cameron. That's right, folks; similar to a John Conner reprogramming a Terminator, only James Cameron could construct a film powerful enough to unseat James Cameron. And once Avatar: The Way of Water drops in December this year, he might do it again. 

In the video linked above, Cameron walks viewers through the writing process behind both Titanic and Avatar and their differences.