NavList:

I didn't watch more than a few seconds of the video, but yeah, it's a legitimate complaint about the original film. James Cameron and his team spent a fortune and considerable effort getting tiny details right, but when it came to the sky, they used a rather random pattern which was obviously then flipped and doubled. And this was at a point of high drama when Jack is about to die. I noticed it right away myself when I first saw the film. Of course many movies use random star patterns. That's not unusual. But it was such a contrast to the care and ettention to detail in the rest of the film. They had all the tools and information available to get it right, but they got it so badly wrong. My guess was that the 'sky full of fake stars' in the original film was a placeholder special effect which was supposed to be replaced in a later edit.

Later in that video that you linked, did they mention that Cameron fixed that sky when the film was re-released? I haven't seen the revision yet, but I would assume that they got it right on the second try. It is, after all, trivial to simulate the sky when you know the exact location and time, as we do with the sinking of Titanic. Here's an entertainment article from a couple of years ago discussing the change. The article says, " the starry sky above her was . . . all wrong. Most likely, no one noticed." But of course other people noticed. It's true that the vast majority of movie-goers would not have noticed because we are predominantly an urban society today, largely disconnected from most aspects of the natural world, and especially the night sky. Yet plenty of people with some interest in the night sky spotted this 'glaring error' right away. It doesn't take a rock star astrophysicist to spot fake stars.

-FER