The "documentary"-style look at the first film (here, the War of 1996) gives background for the upcoming movie, and helps to bridge the nearly 20-year gap between the release of Independence Day and the release of its forthcoming sequel.
Centered around the "War of 1996," it gives clues as to what happened to beloved characters from the first movie...including the death of Will Smith's character, Colonel Steven Hiller.
According to a timeline found on the viral site, "While test piloting the ESD's first alien hybrid fighter, an unknown malfunction causes the untimely death of Col. Hiller. Hiller's valor in the War of '96 made him a beloved global icon whose selfless assault against the alien mothership lead directly to the enemy's defeat. He is survived by his wife Jasmine and his son Dylan."'
Having died in 2007 seemingly precludes Smith from making even a cameo appearance in the new film.
Dylan, of course, is expected to be a character in the new film.
Independence Day was just the beginning. We always knew they were coming back. After that film redefined the event movie genre, the next epic chapter in the Independence Day universe delivers global spectacle on an unimaginable scale. Using recovered alien technology, the nations of Earth have collaborated on an immense defense program to protect the planet. But nothing can prepare us for the aliens’ advanced and unprecedented force. Only the ingenuity of a few brave men and women can bring our world back from the brink of extinction.