The Importance of Finding Causes That Are Underserved

One of effective altruism things is that you should find causes that are underserved where there's low hanging fruit and so you can have like an outsized effect on it. This way of thinking I think is wrong because in real life given the way that knowledge is and the way that ignorance exists, doesn't saving the world from catastrophic extinction make something more fun? We could use physics to predict what a giant asteroid heading towards the earth would do but those are rare cases. There won't be a faction that resists trying to stop the asteroid couldn't.