It didn't show the ship sinking properly. They went to see Leo and hear Celine and look at Kate's dress. They went to be moved and impressed by a story, by images and sounds and characters. That's what Hollywood producers aim for. It doesn't mean they're evil for it.
Every business is in business to make money.
And if movie studios felt obliged to always tell the whole truth, they would likely go out of business, because often we don't want to hear the whole truth. Or, it goes against what we want to believe. This isn't to say that the family and neighbors involved are wrong for feeling hurt by the motion picture companies that twist and edit their lives for profit. It isn't exactly an affirmation of human dignity when a person's life gets edited for the silver screen. But by now, we really should see it coming.