"Save the world" and "make the world a better place" are probably just things employers tell you to get you to work for cheap.
Or maybe it'll just make you some money so you can raise some kids, have some pet rabbits, and be active in your local community.
There's more than one way to get meaning in life.
We like watching Star Wars and Lord of the Rings and whatever, but we wouldn't want to actually fight Darth Vader or slog through Mordor. That would cause major burnout!