If your utility function is based on total humanity lifetime value, and you're completely altruistic, sure. Most people don't seem to be all that altruistic, though. If I had to choose between saving one or two human beings, I would choose the latter option, but I'd never sacrifice myself to save a measly two humans.

That seems like a bias/heuristic; people are known to be biased in favor of themseves, and there is instrumental value in more life to help people with.