Which is funny, because throughout the film, we see a Time magazine cover that names him a savior, with his own addition of a question mark after that very word.
Much like Richard Matheson intended, Dr. Robert Neville is the boogeyman for the Hemocytes.
It’s as if the film is not only building his character with that moment, it’s also openly asking us to question our feelings for this character, and ultimately his ending.
Instead of sacrificing himself out of spite as a savior of humanity, in the alternate ending, he opts to leave the Hemocytes alone having now seen them for what they truly are.